This commit is contained in:
Nicolo Fusi 2013-02-12 18:04:07 +00:00
commit 8761f72c59
66 changed files with 1888 additions and 6647 deletions

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@ -7,5 +7,5 @@ import models
import inference import inference
import util import util
import examples import examples
#import examples TODO: discuss!
from core import priors from core import priors
import likelihoods

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@ -10,6 +10,7 @@ from parameterised import parameterised, truncate_pad
import priors import priors
from ..util.linalg import jitchol from ..util.linalg import jitchol
from ..inference import optimization from ..inference import optimization
from .. import likelihoods
class model(parameterised): class model(parameterised):
def __init__(self): def __init__(self):
@ -82,7 +83,7 @@ class model(parameterised):
def get(self,name, return_names=False): def get(self,name, return_names=False):
""" """
Get a model parameter by name. The name is applied as a regular expression and all parameters that match that regular expression are returned. Get a model parameter by name. The name is applied as a regular expression and all parameters that match that regular expression are returned.
""" """
matches = self.grep_param_names(name) matches = self.grep_param_names(name)
if len(matches): if len(matches):
@ -107,7 +108,7 @@ class model(parameterised):
def get_gradient(self,name, return_names=False): def get_gradient(self,name, return_names=False):
""" """
Get model gradient(s) by name. The name is applied as a regular expression and all parameters that match that regular expression are returned. Get model gradient(s) by name. The name is applied as a regular expression and all parameters that match that regular expression are returned.
""" """
matches = self.grep_param_names(name) matches = self.grep_param_names(name)
if len(matches): if len(matches):
@ -303,54 +304,62 @@ class model(parameterised):
return '\n'.join(s) return '\n'.join(s)
def checkgrad(self, verbose=False, include_priors=False, step=1e-6, tolerance = 1e-3, return_ratio=False, *args): def checkgrad(self, verbose=False, include_priors=False, step=1e-6, tolerance = 1e-3):
""" """
Check the gradient of the model by comparing to a numerical estimate. Check the gradient of the model by comparing to a numerical estimate.
If the overall gradient fails, invividual components are tested. If the verbose flag is passed, invividual components are tested (and printed)
:param verbose: If True, print a "full" checking of each parameter
:type verbose: bool
:param step: The size of the step around which to linearise the objective
:type step: float (defaul 1e-6)
:param tolerance: the tolerance allowed (see note)
:type tolerance: float (default 1e-3)
Note:-
The gradient is considered correct if the ratio of the analytical
and numerical gradients is within <tolerance> of unity.
""" """
x = self._get_params_transformed().copy() x = self._get_params_transformed().copy()
#choose a random direction to step in: if not verbose:
dx = step*np.sign(np.random.uniform(-1,1,x.size)) #just check the global ratio
dx = step*np.sign(np.random.uniform(-1,1,x.size))
#evaulate around the point x #evaulate around the point x
self._set_params_transformed(x+dx) self._set_params_transformed(x+dx)
f1,g1 = self.log_likelihood() + self.log_prior(), self._log_likelihood_gradients_transformed() f1,g1 = self.log_likelihood() + self.log_prior(), self._log_likelihood_gradients_transformed()
self._set_params_transformed(x-dx) self._set_params_transformed(x-dx)
f2,g2 = self.log_likelihood() + self.log_prior(), self._log_likelihood_gradients_transformed() f2,g2 = self.log_likelihood() + self.log_prior(), self._log_likelihood_gradients_transformed()
self._set_params_transformed(x) self._set_params_transformed(x)
gradient = self._log_likelihood_gradients_transformed() gradient = self._log_likelihood_gradients_transformed()
numerical_gradient = (f1-f2)/(2*dx) numerical_gradient = (f1-f2)/(2*dx)
global_ratio = (f1-f2)/(2*np.dot(dx,gradient)) global_ratio = (f1-f2)/(2*np.dot(dx,gradient))
if verbose:
print "Gradient ratio = ", global_ratio, '\n'
sys.stdout.flush()
if (np.abs(1.-global_ratio)<tolerance) and not np.isnan(global_ratio): if (np.abs(1.-global_ratio)<tolerance) and not np.isnan(global_ratio):
if verbose: return True
print 'Gradcheck passed' else:
return False
else: else:
if verbose: #check the gradient of each parameter individually, and do some pretty printing
print "Global check failed. Testing individual gradients\n" try:
names = self._get_param_names_transformed()
except NotImplementedError:
names = ['Variable %i'%i for i in range(len(x))]
try: # Prepare for pretty-printing
names = self._get_param_names_transformed() header = ['Name', 'Ratio', 'Difference', 'Analytical', 'Numerical']
except NotImplementedError: max_names = max([len(names[i]) for i in range(len(names))] + [len(header[0])])
names = ['Variable %i'%i for i in range(len(x))] float_len = 10
cols = [max_names]
# Prepare for pretty-printing cols.extend([max(float_len, len(header[i])) for i in range(1, len(header))])
header = ['Name', 'Ratio', 'Difference', 'Analytical', 'Numerical'] cols = np.array(cols) + 5
max_names = max([len(names[i]) for i in range(len(names))] + [len(header[0])]) header_string = ["{h:^{col}}".format(h = header[i], col = cols[i]) for i in range(len(cols))]
float_len = 10 header_string = map(lambda x: '|'.join(x), [header_string])
cols = [max_names] separator = '-'*len(header_string[0])
cols.extend([max(float_len, len(header[i])) for i in range(1, len(header))]) print '\n'.join([header_string[0], separator])
cols = np.array(cols) + 5
header_string = ["{h:^{col}}".format(h = header[i], col = cols[i]) for i in range(len(cols))]
header_string = map(lambda x: '|'.join(x), [header_string])
separator = '-'*len(header_string[0])
print '\n'.join([header_string[0], separator])
for i in range(len(x)): for i in range(len(x)):
xx = x.copy() xx = x.copy()
@ -368,27 +377,52 @@ class model(parameterised):
ratio = (f1-f2)/(2*step*gradient) ratio = (f1-f2)/(2*step*gradient)
difference = np.abs((f1-f2)/2/step - gradient) difference = np.abs((f1-f2)/2/step - gradient)
if verbose: if (np.abs(ratio-1)<tolerance):
if (np.abs(ratio-1)<tolerance): formatted_name = "\033[92m {0} \033[0m".format(names[i])
formatted_name = "\033[92m {0} \033[0m".format(names[i]) else:
else: formatted_name = "\033[91m {0} \033[0m".format(names[i])
formatted_name = "\033[91m {0} \033[0m".format(names[i]) r = '%.6f' % float(ratio)
r = '%.6f' % float(ratio) d = '%.6f' % float(difference)
d = '%.6f' % float(difference) g = '%.6f' % gradient
g = '%.6f' % gradient ng = '%.6f' % float(numerical_gradient)
ng = '%.6f' % float(numerical_gradient) grad_string = "{0:^{c0}}|{1:^{c1}}|{2:^{c2}}|{3:^{c3}}|{4:^{c4}}".format(formatted_name,r,d,g, ng, c0 = cols[0]+9, c1 = cols[1], c2 = cols[2], c3 = cols[3], c4 = cols[4])
grad_string = "{0:^{c0}}|{1:^{c1}}|{2:^{c2}}|{3:^{c3}}|{4:^{c4}}".format(formatted_name,r,d,g, ng, c0 = cols[0]+9, c1 = cols[1], c2 = cols[2], c3 = cols[3], c4 = cols[4]) print grad_string
print grad_string
if verbose: def EPEM(self,epsilon=.1,**kwargs):
print '' """
TODO: Should this not bein the GP class?
Expectation maximization for Expectation Propagation.
if return_ratio: kwargs are passed to the optimize function. They can be:
return global_ratio
:epsilon: convergence criterion
:max_f_eval: maximum number of function evaluations
:messages: whether to display during optimisation
:param optimzer: whice optimizer to use (defaults to self.preferred optimizer)
:type optimzer: string TODO: valid strings?
"""
assert isinstance(self.likelihood,likelihoods.EP), "EM is not available for Gaussian likelihoods"
log_change = epsilon + 1.
self.log_likelihood_record = []
self.gp_params_record = []
self.ep_params_record = []
iteration = 0
last_value = -np.exp(1000)
while log_change > epsilon or not iteration:
print 'EM iteration %s' %iteration
self.update_likelihood_approximation()
self.optimize(**kwargs)
new_value = self.log_likelihood()
log_change = new_value - last_value
if log_change > epsilon:
self.log_likelihood_record.append(new_value)
self.gp_params_record.append(self._get_params())
#self.ep_params_record.append((self.beta,self.Y,self.Z_ep))
last_value = new_value
else: else:
return False convergence = False
#self.beta, self.Y, self.Z_ep = self.ep_params_record[-1]
if return_ratio: self._set_params(self.gp_params_record[-1])
return global_ratio print "Log-likelihood decrement: %s \nLast iteration discarded." %log_change
else: iteration += 1
return True

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@ -102,6 +102,11 @@ class parameterised(object):
else: else:
return expr return expr
def Nparam_transformed(self):
ties = 0
for ar in self.tied_indices:
ties += ar.size - 1
return self.Nparam - len(self.constrained_fixed_indices) - ties
def constrain_positive(self, which): def constrain_positive(self, which):
""" """
@ -149,8 +154,6 @@ class parameterised(object):
def constrain_negative(self,which): def constrain_negative(self,which):
""" """
Set negative constraints. Set negative constraints.

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@ -17,7 +17,7 @@ K = k.K(X)
Y = np.random.multivariate_normal(np.zeros(N),K,D).T Y = np.random.multivariate_normal(np.zeros(N),K,D).T
# k = GPy.kern.rbf(Q) + GPy.kern.bias(Q) + GPy.kern.white(Q, 0.00001) # k = GPy.kern.rbf(Q) + GPy.kern.bias(Q) + GPy.kern.white(Q, 0.00001)
k = GPy.kern.linear(Q, ARD = True) + GPy.kern.white(Q) k = GPy.kern.rbf(Q, ARD = False) + GPy.kern.white(Q, 0.00001)
m = GPy.models.Bayesian_GPLVM(Y, Q, kernel = k, M=M) m = GPy.models.Bayesian_GPLVM(Y, Q, kernel = k, M=M)
m.constrain_positive('(rbf|bias|noise|white|S)') m.constrain_positive('(rbf|bias|noise|white|S)')
# m.constrain_fixed('S', 1) # m.constrain_fixed('S', 1)

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@ -3,16 +3,15 @@
""" """
Simple Gaussian Processes classification Gaussian Processes classification
""" """
import pylab as pb import pylab as pb
import numpy as np import numpy as np
import GPy import GPy
default_seed=10000 default_seed=10000
######################################
## 2 dimensional example def crescent_data(model_type='Full', inducing=10, seed=default_seed): #FIXME
def crescent_data(model_type='Full', inducing=10, seed=default_seed):
"""Run a Gaussian process classification on the crescent data. The demonstration calls the basic GP classification model and uses EP to approximate the likelihood. """Run a Gaussian process classification on the crescent data. The demonstration calls the basic GP classification model and uses EP to approximate the likelihood.
:param model_type: type of model to fit ['Full', 'FITC', 'DTC']. :param model_type: type of model to fit ['Full', 'FITC', 'DTC'].
@ -21,20 +20,28 @@ def crescent_data(model_type='Full', inducing=10, seed=default_seed):
:param inducing : number of inducing variables (only used for 'FITC' or 'DTC'). :param inducing : number of inducing variables (only used for 'FITC' or 'DTC').
:type inducing: int :type inducing: int
""" """
data = GPy.util.datasets.crescent_data(seed=seed) data = GPy.util.datasets.crescent_data(seed=seed)
likelihood = GPy.inference.likelihoods.probit(data['Y'])
# Kernel object
kernel = GPy.kern.rbf(data['X'].shape[1])
# Likelihood object
distribution = GPy.likelihoods.likelihood_functions.probit()
likelihood = GPy.likelihoods.EP(data['Y'],distribution)
if model_type=='Full': if model_type=='Full':
m = GPy.models.GP_EP(data['X'],likelihood) m = GPy.models.GP(data['X'],likelihood,kernel)
else: else:
# create sparse GP EP model # create sparse GP EP model
m = GPy.models.sparse_GP_EP(data['X'],likelihood=likelihood,inducing=inducing,ep_proxy=model_type) m = GPy.models.sparse_GP_EP(data['X'],likelihood=likelihood,inducing=inducing,ep_proxy=model_type)
m.approximate_likelihood() m.update_likelihood_approximation()
print(m) print(m)
# optimize # optimize
m.em() m.optimize()
print(m) print(m)
# plot # plot
@ -42,54 +49,67 @@ def crescent_data(model_type='Full', inducing=10, seed=default_seed):
return m return m
def oil(): def oil():
"""Run a Gaussian process classification on the oil data. The demonstration calls the basic GP classification model and uses EP to approximate the likelihood.""" """
Run a Gaussian process classification on the oil data. The demonstration calls the basic GP classification model and uses EP to approximate the likelihood.
"""
data = GPy.util.datasets.oil() data = GPy.util.datasets.oil()
likelihood = GPy.inference.likelihoods.probit(data['Y'][:, 0:1]) # Kernel object
kernel = GPy.kern.rbf(12)
# create simple GP model # Likelihood object
m = GPy.models.GP_EP(data['X'],likelihood) distribution = GPy.likelihoods.likelihood_functions.probit()
likelihood = GPy.likelihoods.EP(data['Y'][:, 0:1],distribution)
# contrain all parameters to be positive # Create GP model
m = GPy.models.GP(data['X'],likelihood=likelihood,kernel=kernel)
# Contrain all parameters to be positive
m.constrain_positive('') m.constrain_positive('')
m.tie_param('lengthscale') m.tie_param('lengthscale')
m.approximate_likelihood() m.update_likelihood_approximation()
# optimize # Optimize
m.optimize() m.optimize()
# plot
#m.plot()
print(m) print(m)
return m return m
def toy_linear_1d_classification(model_type='Full', inducing=4, seed=default_seed): def toy_linear_1d_classification(seed=default_seed):
"""Simple 1D classification example. """
:param model_type: type of model to fit ['Full', 'FITC', 'DTC']. Simple 1D classification example
:param seed : seed value for data generation (default is 4). :param seed : seed value for data generation (default is 4).
:type seed: int :type seed: int
:param inducing : number of inducing variables (only used for 'FITC' or 'DTC').
:type inducing: int
""" """
data = GPy.util.datasets.toy_linear_1d_classification(seed=seed) data = GPy.util.datasets.toy_linear_1d_classification(seed=seed)
likelihood = GPy.inference.likelihoods.probit(data['Y'][:, 0:1]) Y = data['Y'][:, 0:1]
assert model_type in ('Full','DTC','FITC') Y[Y == -1] = 0
# create simple GP model # Kernel object
if model_type=='Full': kernel = GPy.kern.rbf(1)
m = GPy.models.simple_GP_EP(data['X'],likelihood)
else:
# create sparse GP EP model
m = GPy.models.sparse_GP_EP(data['X'],likelihood=likelihood,inducing=inducing,ep_proxy=model_type)
m.constrain_positive('var') # Likelihood object
m.constrain_positive('len') distribution = GPy.likelihoods.likelihood_functions.probit()
m.tie_param('lengthscale') likelihood = GPy.likelihoods.EP(Y,distribution)
m.approximate_likelihood()
# Optimize and plot # Model definition
m.em(plot_all=False) # EM algorithm m = GPy.models.GP(data['X'],likelihood=likelihood,kernel=kernel)
# Optimize
"""
EPEM runs a loop that consists of two steps:
1) EP likelihood approximation:
m.update_likelihood_approximation()
2) Parameters optimization:
m.optimize()
"""
m.EPEM()
# Plot
pb.subplot(211)
m.plot_f()
pb.subplot(212)
m.plot() m.plot()
print(m) print(m)
return m return m

47
GPy/examples/poisson.py Normal file
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@ -0,0 +1,47 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
"""
Gaussian Processes + Expectation Propagation - Poisson Likelihood
"""
import pylab as pb
import numpy as np
import GPy
default_seed=10000
def toy_1d(seed=default_seed):
"""
Simple 1D classification example
:param seed : seed value for data generation (default is 4).
:type seed: int
"""
X = np.arange(0,100,5)[:,None]
F = np.round(np.sin(X/18.) + .1*X) + np.arange(5,25)[:,None]
E = np.random.randint(-5,5,20)[:,None]
Y = F + E
kernel = GPy.kern.rbf(1)
distribution = GPy.likelihoods.likelihood_functions.Poisson()
likelihood = GPy.likelihoods.EP(Y,distribution)
m = GPy.models.GP(X,likelihood,kernel)
m.ensure_default_constraints()
# Approximate likelihood
m.update_likelihood_approximation()
# Optimize and plot
m.optimize()
#m.EPEM FIXME
print m
# Plot
pb.subplot(211)
m.plot_f() #GP plot
pb.subplot(212)
m.plot() #Output plot
return m

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@ -0,0 +1,60 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
"""
Sparse Gaussian Processes regression with an RBF kernel
"""
import pylab as pb
import numpy as np
import GPy
np.random.seed(2)
pb.ion()
N = 500
M = 5
pb.close('all')
######################################
## 1 dimensional example
# sample inputs and outputs
X = np.random.uniform(-3.,3.,(N,1))
#Y = np.sin(X)+np.random.randn(N,1)*0.05
F = np.sin(X)+np.random.randn(N,1)*0.05
Y = np.ones([F.shape[0],1])
Y[F<0] = -1
likelihood = GPy.inference.likelihoods.probit(Y)
# construct kernel
rbf = GPy.kern.rbf(1)
noise = GPy.kern.white(1)
kernel = rbf + noise
# create simple GP model
#m = GPy.models.sparse_GP(X,Y=None, kernel=kernel, M=M,likelihood= likelihood)
# contrain all parameters to be positive
#m.constrain_fixed('prec',100.)
m = GPy.models.sparse_GP(X, Y, kernel, M=M)
m.ensure_default_constraints()
#if not isinstance(m.likelihood,GPy.inference.likelihoods.gaussian):
# m.approximate_likelihood()
print m.checkgrad()
m.optimize('tnc', messages = 1)
m.plot(samples=3)
print m
n = GPy.models.sparse_GP(X,Y=None, kernel=kernel, M=M,likelihood= likelihood)
n.ensure_default_constraints()
if not isinstance(n.likelihood,GPy.inference.likelihoods.gaussian):
n.approximate_likelihood()
print n.checkgrad()
pb.figure()
n.plot()
"""
m = GPy.models.sparse_GP_regression(X, Y, kernel, M=M)
m.ensure_default_constraints()
print m.checkgrad()
"""

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@ -1,240 +0,0 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
import random
from scipy import stats, linalg
from .likelihoods import likelihood
from ..core import model
from ..util.linalg import pdinv,mdot,jitchol
from ..util.plot import gpplot
from .. import kern
class EP_base:
"""
Expectation Propagation.
This is just the base class for expectation propagation. We'll extend it for full and sparse EP.
"""
def __init__(self,likelihood,epsilon=1e-3,powerep=[1.,1.]):
self.likelihood = likelihood
self.epsilon = epsilon
self.eta, self.delta = powerep
self.jitter = 1e-12
#Initial values - Likelihood approximation parameters:
#p(y|f) = t(f|tau_tilde,v_tilde)
self.restart_EP()
def restart_EP(self):
"""
Set the EP approximation to initial state
"""
self.tau_tilde = np.zeros(self.N)
self.v_tilde = np.zeros(self.N)
self.mu = np.zeros(self.N)
class Full(EP_base):
"""
:param likelihood: Output's likelihood (e.g. probit)
:type likelihood: GPy.inference.likelihood instance
:param K: prior covariance matrix
:type K: np.ndarray (N x N)
:param likelihood: Output's likelihood (e.g. probit)
:type likelihood: GPy.inference.likelihood instance
:param epsilon: Convergence criterion, maximum squared difference allowed between mean updates to stop iterations (float)
:param powerep: Power-EP parameters (eta,delta) - 2x1 numpy array (floats)
"""
def __init__(self,K,likelihood,*args,**kwargs):
assert K.shape[0] == K.shape[1]
self.K = K
self.N = self.K.shape[0]
EP_base.__init__(self,likelihood,*args,**kwargs)
def fit_EP(self,messages=False):
"""
The expectation-propagation algorithm.
For nomenclature see Rasmussen & Williams 2006 (pag. 52-60)
"""
#Prior distribution parameters: p(f|X) = N(f|0,K)
#self.K = self.kernel.K(self.X,self.X)
#Initial values - Posterior distribution parameters: q(f|X,Y) = N(f|mu,Sigma)
self.mu=np.zeros(self.N)
self.Sigma=self.K.copy()
"""
Initial values - Cavity distribution parameters:
q_(f|mu_,sigma2_) = Product{q_i(f|mu_i,sigma2_i)}
sigma_ = 1./tau_
mu_ = v_/tau_
"""
self.tau_ = np.empty(self.N,dtype=np.float64)
self.v_ = np.empty(self.N,dtype=np.float64)
#Initial values - Marginal moments
z = np.empty(self.N,dtype=np.float64)
self.Z_hat = np.empty(self.N,dtype=np.float64)
phi = np.empty(self.N,dtype=np.float64)
mu_hat = np.empty(self.N,dtype=np.float64)
sigma2_hat = np.empty(self.N,dtype=np.float64)
#Approximation
epsilon_np1 = self.epsilon + 1.
epsilon_np2 = self.epsilon + 1.
self.iterations = 0
self.np1 = [self.tau_tilde.copy()]
self.np2 = [self.v_tilde.copy()]
while epsilon_np1 > self.epsilon or epsilon_np2 > self.epsilon:
update_order = np.random.permutation(self.N)
for i in update_order:
#Cavity distribution parameters
self.tau_[i] = 1./self.Sigma[i,i] - self.eta*self.tau_tilde[i]
self.v_[i] = self.mu[i]/self.Sigma[i,i] - self.eta*self.v_tilde[i]
#Marginal moments
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.likelihood.moments_match(i,self.tau_[i],self.v_[i])
#Site parameters update
Delta_tau = self.delta/self.eta*(1./sigma2_hat[i] - 1./self.Sigma[i,i])
Delta_v = self.delta/self.eta*(mu_hat[i]/sigma2_hat[i] - self.mu[i]/self.Sigma[i,i])
self.tau_tilde[i] = self.tau_tilde[i] + Delta_tau
self.v_tilde[i] = self.v_tilde[i] + Delta_v
#Posterior distribution parameters update
si=self.Sigma[:,i].reshape(self.N,1)
self.Sigma = self.Sigma - Delta_tau/(1.+ Delta_tau*self.Sigma[i,i])*np.dot(si,si.T)
self.mu = np.dot(self.Sigma,self.v_tilde)
self.iterations += 1
#Sigma recomptutation with Cholesky decompositon
Sroot_tilde_K = np.sqrt(self.tau_tilde)[:,None]*(self.K)
B = np.eye(self.N) + np.sqrt(self.tau_tilde)[None,:]*Sroot_tilde_K
L = jitchol(B)
V,info = linalg.flapack.dtrtrs(L,Sroot_tilde_K,lower=1)
self.Sigma = self.K - np.dot(V.T,V)
self.mu = np.dot(self.Sigma,self.v_tilde)
epsilon_np1 = np.mean(self.tau_tilde-self.np1[-1]**2)
epsilon_np2 = np.mean(self.v_tilde-self.np2[-1]**2)
self.np1.append(self.tau_tilde.copy())
self.np2.append(self.v_tilde.copy())
if messages:
print "EP iteration %i, epsiolon %d"%(self.iterations,epsilon_np1)
class FITC(EP_base):
"""
:param likelihood: Output's likelihood (e.g. probit)
:type likelihood: GPy.inference.likelihood instance
:param Knn_diag: The diagonal elements of Knn is a 1D vector
:param Kmn: The 'cross' variance between inducing inputs and data
:param Kmm: the covariance matrix of the inducing inputs
:param likelihood: Output's likelihood (e.g. probit)
:type likelihood: GPy.inference.likelihood instance
:param epsilon: Convergence criterion, maximum squared difference allowed between mean updates to stop iterations (float)
:param powerep: Power-EP parameters (eta,delta) - 2x1 numpy array (floats)
"""
def __init__(self,likelihood,Knn_diag,Kmn,Kmm,*args,**kwargs):
self.Knn_diag = Knn_diag
self.Kmn = Kmn
self.Kmm = Kmm
self.M = self.Kmn.shape[0]
self.N = self.Kmn.shape[1]
assert self.M <= self.N, 'The number of inducing inputs must be smaller than the number of observations'
assert len(Knn_diag) == self.N, 'Knn_diagonal has size different from N'
EP_base.__init__(self,likelihood,*args,**kwargs)
def fit_EP(self):
"""
The expectation-propagation algorithm with sparse pseudo-input.
For nomenclature see Naish-Guzman and Holden, 2008.
"""
"""
Prior approximation parameters:
q(f|X) = int_{df}{N(f|KfuKuu_invu,diag(Kff-Qff)*N(u|0,Kuu)} = N(f|0,Sigma0)
Sigma0 = diag(Knn-Qnn) + Qnn, Qnn = Knm*Kmmi*Kmn
"""
self.Kmmi, self.Kmm_hld = pdinv(self.Kmm)
self.P0 = self.Kmn.T
self.KmnKnm = np.dot(self.P0.T, self.P0)
self.KmmiKmn = np.dot(self.Kmmi,self.P0.T)
self.Qnn_diag = np.sum(self.P0.T*self.KmmiKmn,-2)
self.Diag0 = self.Knn_diag - self.Qnn_diag
self.R0 = jitchol(self.Kmmi).T
"""
Posterior approximation: q(f|y) = N(f| mu, Sigma)
Sigma = Diag + P*R.T*R*P.T + K
mu = w + P*gamma
"""
self.w = np.zeros(self.N)
self.gamma = np.zeros(self.M)
self.mu = np.zeros(self.N)
self.P = self.P0.copy()
self.R = self.R0.copy()
self.Diag = self.Diag0.copy()
self.Sigma_diag = self.Knn_diag
"""
Initial values - Cavity distribution parameters:
q_(g|mu_,sigma2_) = Product{q_i(g|mu_i,sigma2_i)}
sigma_ = 1./tau_
mu_ = v_/tau_
"""
self.tau_ = np.empty(self.N,dtype=np.float64)
self.v_ = np.empty(self.N,dtype=np.float64)
#Initial values - Marginal moments
z = np.empty(self.N,dtype=np.float64)
self.Z_hat = np.empty(self.N,dtype=np.float64)
phi = np.empty(self.N,dtype=np.float64)
mu_hat = np.empty(self.N,dtype=np.float64)
sigma2_hat = np.empty(self.N,dtype=np.float64)
#Approximation
epsilon_np1 = 1
epsilon_np2 = 1
self.iterations = 0
self.np1 = [self.tau_tilde.copy()]
self.np2 = [self.v_tilde.copy()]
while epsilon_np1 > self.epsilon or epsilon_np2 > self.epsilon:
update_order = np.arange(self.N)
random.shuffle(update_order)
for i in update_order:
#Cavity distribution parameters
self.tau_[i] = 1./self.Sigma_diag[i] - self.eta*self.tau_tilde[i]
self.v_[i] = self.mu[i]/self.Sigma_diag[i] - self.eta*self.v_tilde[i]
#Marginal moments
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.likelihood.moments_match(i,self.tau_[i],self.v_[i])
#Site parameters update
Delta_tau = self.delta/self.eta*(1./sigma2_hat[i] - 1./self.Sigma_diag[i])
Delta_v = self.delta/self.eta*(mu_hat[i]/sigma2_hat[i] - self.mu[i]/self.Sigma_diag[i])
self.tau_tilde[i] = self.tau_tilde[i] + Delta_tau
self.v_tilde[i] = self.v_tilde[i] + Delta_v
#Posterior distribution parameters update
dtd1 = Delta_tau*self.Diag[i] + 1.
dii = self.Diag[i]
self.Diag[i] = dii - (Delta_tau * dii**2.)/dtd1
pi_ = self.P[i,:].reshape(1,self.M)
self.P[i,:] = pi_ - (Delta_tau*dii)/dtd1 * pi_
Rp_i = np.dot(self.R,pi_.T)
RTR = np.dot(self.R.T,np.dot(np.eye(self.M) - Delta_tau/(1.+Delta_tau*self.Sigma_diag[i]) * np.dot(Rp_i,Rp_i.T),self.R))
self.R = jitchol(RTR).T
self.w[i] = self.w[i] + (Delta_v - Delta_tau*self.w[i])*dii/dtd1
self.gamma = self.gamma + (Delta_v - Delta_tau*self.mu[i])*np.dot(RTR,self.P[i,:].T)
self.RPT = np.dot(self.R,self.P.T)
self.Sigma_diag = self.Diag + np.sum(self.RPT.T*self.RPT.T,-1)
self.mu = self.w + np.dot(self.P,self.gamma)
self.iterations += 1
#Sigma recomptutation with Cholesky decompositon
self.Diag = self.Diag0/(1.+ self.Diag0 * self.tau_tilde)
self.P = (self.Diag / self.Diag0)[:,None] * self.P0
self.RPT0 = np.dot(self.R0,self.P0.T)
L = jitchol(np.eye(self.M) + np.dot(self.RPT0,(1./self.Diag0 - self.Diag/(self.Diag0**2))[:,None]*self.RPT0.T))
self.R,info = linalg.flapack.dtrtrs(L,self.R0,lower=1)
self.RPT = np.dot(self.R,self.P.T)
self.Sigma_diag = self.Diag + np.sum(self.RPT.T*self.RPT.T,-1)
self.w = self.Diag * self.v_tilde
self.gamma = np.dot(self.R.T, np.dot(self.RPT,self.v_tilde))
self.mu = self.w + np.dot(self.P,self.gamma)
epsilon_np1 = sum((self.tau_tilde-self.np1[-1])**2)/self.N
epsilon_np2 = sum((self.v_tilde-self.np2[-1])**2)/self.N
self.np1.append(self.tau_tilde.copy())
self.np2.append(self.v_tilde.copy())

View file

@ -1,219 +0,0 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
from scipy import stats
import scipy as sp
import pylab as pb
from ..util.plot import gpplot
class likelihood:
def __init__(self,Y,location=0,scale=1):
"""
Likelihood class for doing Expectation propagation
:param Y: observed output (Nx1 numpy.darray)
..Note:: Y values allowed depend on the likelihood used
"""
self.Y = Y
self.N = self.Y.shape[0]
self.location = location
self.scale = scale
def plot1Da(self,X_new,Mean_new,Var_new,X_u,Mean_u,Var_u):
"""
Plot the predictive distribution of the GP model for 1-dimensional inputs
:param X_new: The points at which to make a prediction
:param Mean_new: mean values at X_new
:param Var_new: variance values at X_new
:param X_u: input (inducing) points used to train the model
:param Mean_u: mean values at X_u
:param Var_new: variance values at X_u
"""
assert X_new.shape[1] == 1, 'Number of dimensions must be 1'
gpplot(X_new,Mean_new,Var_new)
pb.errorbar(X_u,Mean_u,2*np.sqrt(Var_u),fmt='r+')
pb.plot(X_u,Mean_u,'ro')
def plot2D(self,X,X_new,F_new,U=None):
"""
Predictive distribution of the fitted GP model for 2-dimensional inputs
:param X_new: The points at which to make a prediction
:param Mean_new: mean values at X_new
:param Var_new: variance values at X_new
:param X_u: input points used to train the model
:param Mean_u: mean values at X_u
:param Var_new: variance values at X_u
"""
N,D = X_new.shape
assert D == 2, 'Number of dimensions must be 2'
n = np.sqrt(N)
x1min = X_new[:,0].min()
x1max = X_new[:,0].max()
x2min = X_new[:,1].min()
x2max = X_new[:,1].max()
pb.imshow(F_new.reshape(n,n),extent=(x1min,x1max,x2max,x2min),vmin=0,vmax=1)
pb.colorbar()
C1 = np.arange(self.N)[self.Y.flatten()==1]
C2 = np.arange(self.N)[self.Y.flatten()==-1]
[pb.plot(X[i,0],X[i,1],'ro') for i in C1]
[pb.plot(X[i,0],X[i,1],'bo') for i in C2]
pb.xlim(x1min,x1max)
pb.ylim(x2min,x2max)
if U is not None:
[pb.plot(a,b,'wo') for a,b in U]
class probit(likelihood):
"""
Probit likelihood
Y is expected to take values in {-1,1}
-----
$$
L(x) = \\Phi (Y_i*f_i)
$$
"""
def moments_match(self,i,tau_i,v_i):
"""
Moments match of the marginal approximation in EP algorithm
:param i: number of observation (int)
:param tau_i: precision of the cavity distribution (float)
:param v_i: mean/variance of the cavity distribution (float)
"""
z = self.Y[i]*v_i/np.sqrt(tau_i**2 + tau_i)
Z_hat = stats.norm.cdf(z)
phi = stats.norm.pdf(z)
mu_hat = v_i/tau_i + self.Y[i]*phi/(Z_hat*np.sqrt(tau_i**2 + tau_i))
sigma2_hat = 1./tau_i - (phi/((tau_i**2+tau_i)*Z_hat))*(z+phi/Z_hat)
return Z_hat, mu_hat, sigma2_hat
def plot1Db(self,X,X_new,F_new,U=None):
assert X.shape[1] == 1, 'Number of dimensions must be 1'
gpplot(X_new,F_new,np.zeros(X_new.shape[0]))
pb.plot(X,(self.Y+1)/2,'kx',mew=1.5)
pb.ylim(-0.2,1.2)
if U is not None:
pb.plot(U,U*0+.5,'r|',mew=1.5,markersize=12)
def predictive_mean(self,mu,variance):
return stats.norm.cdf(mu/np.sqrt(1+variance))
def _log_likelihood_gradients():
raise NotImplementedError
class poisson(likelihood):
"""
Poisson likelihood
Y is expected to take values in {0,1,2,...}
-----
$$
L(x) = \exp(\lambda) * \lambda**Y_i / Y_i!
$$
"""
def moments_match(self,i,tau_i,v_i):
"""
Moments match of the marginal approximation in EP algorithm
:param i: number of observation (int)
:param tau_i: precision of the cavity distribution (float)
:param v_i: mean/variance of the cavity distribution (float)
"""
mu = v_i/tau_i
sigma = np.sqrt(1./tau_i)
def poisson_norm(f):
"""
Product of the likelihood and the cavity distribution
"""
pdf_norm_f = stats.norm.pdf(f,loc=mu,scale=sigma)
rate = np.exp( (f*self.scale)+self.location)
poisson = stats.poisson.pmf(float(self.Y[i]),rate)
return pdf_norm_f*poisson
def log_pnm(f):
"""
Log of poisson_norm
"""
return -(-.5*(f-mu)**2/sigma**2 - np.exp( (f*self.scale)+self.location) + ( (f*self.scale)+self.location)*self.Y[i])
"""
Golden Search and Simpson's Rule
--------------------------------
Simpson's Rule is used to calculate the moments mumerically, it needs a grid of points as input.
Golden Search is used to find the mode in the poisson_norm distribution and define around it the grid for Simpson's Rule
"""
#TODO golden search & simpson's rule can be defined in the general likelihood class, rather than in each specific case.
#Golden search
golden_A = -1 if self.Y[i] == 0 else np.array([np.log(self.Y[i]),mu]).min() #Lower limit
golden_B = np.array([np.log(self.Y[i]),mu]).max() #Upper limit
golden_A = (golden_A - self.location)/self.scale
golden_B = (golden_B - self.location)/self.scale
opt = sp.optimize.golden(log_pnm,brack=(golden_A,golden_B)) #Better to work with log_pnm than with poisson_norm
# Simpson's approximation
width = 3./np.log(max(self.Y[i],2))
A = opt - width #Lower limit
B = opt + width #Upper limit
K = 10*int(np.log(max(self.Y[i],150))) #Number of points in the grid, we DON'T want K to be the same number for every case
h = (B-A)/K # length of the intervals
grid_x = np.hstack([np.linspace(opt-width,opt,K/2+1)[1:-1], np.linspace(opt,opt+width,K/2+1)]) # grid of points (X axis)
x = np.hstack([A,B,grid_x[range(1,K,2)],grid_x[range(2,K-1,2)]]) # grid_x rearranged, just to make Simpson's algorithm easier
zeroth = np.hstack([poisson_norm(A),poisson_norm(B),[4*poisson_norm(f) for f in grid_x[range(1,K,2)]],[2*poisson_norm(f) for f in grid_x[range(2,K-1,2)]]]) # grid of points (Y axis) rearranged like x
first = zeroth*x
second = first*x
Z_hat = sum(zeroth)*h/3 # Zero-th moment
mu_hat = sum(first)*h/(3*Z_hat) # First moment
m2 = sum(second)*h/(3*Z_hat) # Second moment
sigma2_hat = m2 - mu_hat**2 # Second central moment
return float(Z_hat), float(mu_hat), float(sigma2_hat)
def plot1Db(self,X,X_new,F_new,F2_new=None,U=None):
pb.subplot(212)
#gpplot(X_new,F_new,np.sqrt(F2_new))
pb.plot(X_new,F_new)#,np.sqrt(F2_new)) #FIXME
pb.plot(X,self.Y,'kx',mew=1.5)
if U is not None:
pb.plot(U,np.ones(U.shape[0])*self.Y.min()*.8,'r|',mew=1.5,markersize=12)
def predictive_mean(self,mu,variance):
return np.exp(mu*self.scale + self.location)
def predictive_variance(self,mu,variance):
return mu
def _log_likelihood_gradients():
raise NotImplementedError
class gaussian(likelihood):
"""
Gaussian likelihood
Y is expected to take values in (-inf,inf)
"""
def moments_match(self,i,tau_i,v_i):
"""
Moments match of the marginal approximation in EP algorithm
:param i: number of observation (int)
:param tau_i: precision of the cavity distribution (float)
:param v_i: mean/variance of the cavity distribution (float)
"""
mu = v_i/tau_i
sigma = np.sqrt(1./tau_i)
s = 1. if self.Y[i] == 0 else 1./self.Y[i]
sigma2_hat = 1./(1./sigma**2 + 1./s**2)
mu_hat = sigma2_hat*(mu/sigma**2 + self.Y[i]/s**2)
Z_hat = 1./np.sqrt(2*np.pi) * 1./np.sqrt(sigma**2+s**2) * np.exp(-.5*(mu-self.Y[i])**2/(sigma**2 + s**2))
return Z_hat, mu_hat, sigma2_hat
def plot1Db(self,X,X_new,F_new,U=None):
assert X.shape[1] == 1, 'Number of dimensions must be 1'
gpplot(X_new,F_new,np.zeros(X_new.shape[0]))
pb.plot(X,self.Y,'kx',mew=1.5)
if U is not None:
pb.plot(U,np.ones(U.shape[0])*self.Y.min()*.8,'r|',mew=1.5,markersize=12)
def predictive_mean(self,mu,Sigma):
return mu
def _log_likelihood_gradients():
raise NotImplementedError

View file

@ -14,14 +14,14 @@ class Matern32(kernpart):
.. math:: .. math::
k(r) = \sigma^2 (1 + \sqrt{3} r) \exp(- \sqrt{3} r) \qquad \qquad \\text{ where } r = \sqrt{\sum_{i=1}^D \\frac{(x_i-y_i)^2}{\ell_i^2} } k(r) = \\sigma^2 (1 + \\sqrt{3} r) \exp(- \sqrt{3} r) \\ \\ \\ \\ \\text{ where } r = \sqrt{\sum_{i=1}^D \\frac{(x_i-y_i)^2}{\ell_i^2} }
:param D: the number of input dimensions :param D: the number of input dimensions
:type D: int :type D: int
:param variance: the variance :math:`\sigma^2` :param variance: the variance :math:`\sigma^2`
:type variance: float :type variance: float
:param lengthscale: the vector of lengthscale :math:`\ell_i` :param lengthscale: the vector of lengthscale :math:`\ell_i`
:type lengthscale: np.ndarray of size (1,) or (D,) depending on ARD :type lengthscale: array or list of the appropriate size (or float if there is only one lengthscale parameter)
:param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension. :param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension.
:type ARD: Boolean :type ARD: Boolean
:rtype: kernel object :rtype: kernel object
@ -35,17 +35,19 @@ class Matern32(kernpart):
self.Nparam = 2 self.Nparam = 2
self.name = 'Mat32' self.name = 'Mat32'
if lengthscale is not None: if lengthscale is not None:
assert lengthscale.shape == (1,) lengthscale = np.asarray(lengthscale)
assert lengthscale.size == 1, "Only one lengthscale needed for non-ARD kernel"
else: else:
lengthscale = np.ones(1) lengthscale = np.ones(1)
else: else:
self.Nparam = self.D + 1 self.Nparam = self.D + 1
self.name = 'Mat32_ARD' self.name = 'Mat32'
if lengthscale is not None: if lengthscale is not None:
assert lengthscale.shape == (self.D,) lengthscale = np.asarray(lengthscale)
assert lengthscale.size == self.D, "bad number of lengthscales"
else: else:
lengthscale = np.ones(self.D) lengthscale = np.ones(self.D)
self._set_params(np.hstack((variance,lengthscale))) self._set_params(np.hstack((variance,lengthscale.flatten())))
def _get_params(self): def _get_params(self):
"""return the value of the parameters.""" """return the value of the parameters."""
@ -116,9 +118,9 @@ class Matern32(kernpart):
:param F1: vector of derivatives of F :param F1: vector of derivatives of F
:type F1: np.array :type F1: np.array
:param F2: vector of second derivatives of F :param F2: vector of second derivatives of F
:type F2: np.array :type F2: np.array
:param lower,upper: boundaries of the input domain :param lower,upper: boundaries of the input domain
:type lower,upper: floats :type lower,upper: floats
""" """
assert self.D == 1 assert self.D == 1
def L(x,i): def L(x,i):
@ -133,4 +135,3 @@ class Matern32(kernpart):
#print "OLD \n", np.dot(F1lower,F1lower.T), "\n \n" #print "OLD \n", np.dot(F1lower,F1lower.T), "\n \n"
#return(G) #return(G)
return(self.lengthscale**3/(12.*np.sqrt(3)*self.variance) * G + 1./self.variance*np.dot(Flower,Flower.T) + self.lengthscale**2/(3.*self.variance)*np.dot(F1lower,F1lower.T)) return(self.lengthscale**3/(12.*np.sqrt(3)*self.variance) * G + 1./self.variance*np.dot(Flower,Flower.T) + self.lengthscale**2/(3.*self.variance)*np.dot(F1lower,F1lower.T))

View file

@ -13,14 +13,14 @@ class Matern52(kernpart):
.. math:: .. math::
k(r) = \sigma^2 (1 + \sqrt{5} r + \\frac53 r^2) \exp(- \sqrt{5} r) \qquad \qquad \\text{ where } r = \sqrt{\sum_{i=1}^D \\frac{(x_i-y_i)^2}{\ell_i^2} } k(r) = \sigma^2 (1 + \sqrt{5} r + \\frac53 r^2) \exp(- \sqrt{5} r) \ \ \ \ \ \\text{ where } r = \sqrt{\sum_{i=1}^D \\frac{(x_i-y_i)^2}{\ell_i^2} }
:param D: the number of input dimensions :param D: the number of input dimensions
:type D: int :type D: int
:param variance: the variance :math:`\sigma^2` :param variance: the variance :math:`\sigma^2`
:type variance: float :type variance: float
:param lengthscale: the vector of lengthscale :math:`\ell_i` :param lengthscale: the vector of lengthscale :math:`\ell_i`
:type lengthscale: np.ndarray of size (1,) or (D,) depending on ARD :type lengthscale: array or list of the appropriate size (or float if there is only one lengthscale parameter)
:param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension. :param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension.
:type ARD: Boolean :type ARD: Boolean
:rtype: kernel object :rtype: kernel object
@ -33,17 +33,19 @@ class Matern52(kernpart):
self.Nparam = 2 self.Nparam = 2
self.name = 'Mat52' self.name = 'Mat52'
if lengthscale is not None: if lengthscale is not None:
assert lengthscale.shape == (1,) lengthscale = np.asarray(lengthscale)
assert lengthscale.size == 1, "Only one lengthscale needed for non-ARD kernel"
else: else:
lengthscale = np.ones(1) lengthscale = np.ones(1)
else: else:
self.Nparam = self.D + 1 self.Nparam = self.D + 1
self.name = 'Mat52_ARD' self.name = 'Mat52'
if lengthscale is not None: if lengthscale is not None:
assert lengthscale.shape == (self.D,) lengthscale = np.asarray(lengthscale)
assert lengthscale.size == self.D, "bad number of lengthscales"
else: else:
lengthscale = np.ones(self.D) lengthscale = np.ones(self.D)
self._set_params(np.hstack((variance,lengthscale))) self._set_params(np.hstack((variance,lengthscale.flatten())))
def _get_params(self): def _get_params(self):
"""return the value of the parameters.""" """return the value of the parameters."""

View file

@ -13,14 +13,14 @@ class exponential(kernpart):
.. math:: .. math::
k(r) = \sigma^2 \exp(- r) \qquad \qquad \\text{ where } r = \sqrt{\sum_{i=1}^D \\frac{(x_i-y_i)^2}{\ell_i^2} } k(r) = \sigma^2 \exp(- r) \ \ \ \ \ \\text{ where } r = \sqrt{\sum_{i=1}^D \\frac{(x_i-y_i)^2}{\ell_i^2} }
:param D: the number of input dimensions :param D: the number of input dimensions
:type D: int :type D: int
:param variance: the variance :math:`\sigma^2` :param variance: the variance :math:`\sigma^2`
:type variance: float :type variance: float
:param lengthscale: the vector of lengthscale :math:`\ell_i` :param lengthscale: the vector of lengthscale :math:`\ell_i`
:type lengthscale: np.ndarray of size (1,) or (D,) depending on ARD :type lengthscale: array or list of the appropriate size (or float if there is only one lengthscale parameter)
:param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension. :param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension.
:type ARD: Boolean :type ARD: Boolean
:rtype: kernel object :rtype: kernel object
@ -33,17 +33,19 @@ class exponential(kernpart):
self.Nparam = 2 self.Nparam = 2
self.name = 'exp' self.name = 'exp'
if lengthscale is not None: if lengthscale is not None:
assert lengthscale.shape == (1,) lengthscale = np.asarray(lengthscale)
assert lengthscale.size == 1, "Only one lengthscale needed for non-ARD kernel"
else: else:
lengthscale = np.ones(1) lengthscale = np.ones(1)
else: else:
self.Nparam = self.D + 1 self.Nparam = self.D + 1
self.name = 'exp_ARD' self.name = 'exp'
if lengthscale is not None: if lengthscale is not None:
assert lengthscale.shape == (self.D,) lengthscale = np.asarray(lengthscale)
assert lengthscale.size == self.D, "bad number of lengthscales"
else: else:
lengthscale = np.ones(self.D) lengthscale = np.ones(self.D)
self._set_params(np.hstack((variance,lengthscale))) self._set_params(np.hstack((variance,lengthscale.flatten())))
def _get_params(self): def _get_params(self):
"""return the value of the parameters.""" """return the value of the parameters."""
@ -87,7 +89,7 @@ class exponential(kernpart):
dl = self.variance*dvar*dist2M.sum(-1)*invdist dl = self.variance*dvar*dist2M.sum(-1)*invdist
target[1] += np.sum(dl*partial) target[1] += np.sum(dl*partial)
def dKdiag_dtheta(self,partial,X,target): def dKdiag_dtheta(self,partial,X,target):
"""derivative of the diagonal of the covariance matrix with respect to the parameters.""" """derivative of the diagonal of the covariance matrix with respect to the parameters."""
#NB: derivative of diagonal elements wrt lengthscale is 0 #NB: derivative of diagonal elements wrt lengthscale is 0
target[0] += np.sum(partial) target[0] += np.sum(partial)
@ -110,9 +112,9 @@ class exponential(kernpart):
:param F: vector of functions :param F: vector of functions
:type F: np.array :type F: np.array
:param F1: vector of derivatives of F :param F1: vector of derivatives of F
:type F1: np.array :type F1: np.array
:param lower,upper: boundaries of the input domain :param lower,upper: boundaries of the input domain
:type lower,upper: floats :type lower,upper: floats
""" """
assert self.D == 1 assert self.D == 1
def L(x,i): def L(x,i):
@ -124,8 +126,3 @@ class exponential(kernpart):
G[i,j] = G[j,i] = integrate.quad(lambda x : L(x,i)*L(x,j),lower,upper)[0] G[i,j] = G[j,i] = integrate.quad(lambda x : L(x,i)*L(x,j),lower,upper)[0]
Flower = np.array([f(lower) for f in F])[:,None] Flower = np.array([f(lower) for f in F])[:,None]
return(self.lengthscale/2./self.variance * G + 1./self.variance * np.dot(Flower,Flower.T)) return(self.lengthscale/2./self.variance * G + 1./self.variance * np.dot(Flower,Flower.T))

View file

@ -3,6 +3,7 @@
import numpy as np import numpy as np
import pylab as pb
from ..core.parameterised import parameterised from ..core.parameterised import parameterised
from kernpart import kernpart from kernpart import kernpart
import itertools import itertools
@ -155,7 +156,7 @@ class kern(parameterised):
D = K1.D + K2.D D = K1.D + K2.D
newkernparts = [product_orthogonal(k1,k2).parts[0] for k1, k2 in itertools.product(K1.parts,K2.parts)] newkernparts = [product_orthogonal(k1,k2) for k1, k2 in itertools.product(K1.parts,K2.parts)]
slices = [] slices = []
for sl1, sl2 in itertools.product(K1.input_slices,K2.input_slices): for sl1, sl2 in itertools.product(K1.input_slices,K2.input_slices):
@ -235,6 +236,8 @@ class kern(parameterised):
X2 = X X2 = X
target = np.zeros(self.Nparam) target = np.zeros(self.Nparam)
[p.dK_dtheta(partial[s1,s2],X[s1,i_s],X2[s2,i_s],target[ps]) for p,i_s,ps,s1,s2 in zip(self.parts, self.input_slices, self.param_slices, slices1, slices2)] [p.dK_dtheta(partial[s1,s2],X[s1,i_s],X2[s2,i_s],target[ps]) for p,i_s,ps,s1,s2 in zip(self.parts, self.input_slices, self.param_slices, slices1, slices2)]
#TODO: transform the gradients here!
return target return target
def dK_dX(self,partial,X,X2=None,slices1=None,slices2=None): def dK_dX(self,partial,X,X2=None,slices1=None,slices2=None):
@ -372,3 +375,59 @@ class kern(parameterised):
#TODO: there are some extra terms to compute here! #TODO: there are some extra terms to compute here!
return target_mu, target_S return target_mu, target_S
def plot(self, x = None, plot_limits=None,which_functions='all',resolution=None):
if which_functions=='all':
which_functions = [True]*self.Nparts
if self.D == 1:
if x is None:
x = np.zeros((1,1))
else:
x = np.asarray(x)
assert x.size == 1, "The size of the fixed variable x is not 1"
x = x.reshape((1,1))
if plot_limits == None:
xmin, xmax = (x-5).flatten(), (x+5).flatten()
elif len(plot_limits) == 2:
xmin, xmax = plot_limits
else:
raise ValueError, "Bad limits for plotting"
Xnew = np.linspace(xmin,xmax,resolution or 201)[:,None]
Kx = self.K(Xnew,x,slices2=which_functions)
pb.plot(Xnew,Kx)
pb.xlim(xmin,xmax)
pb.xlabel("x")
pb.ylabel("k(x,%0.1f)" %x)
elif self.D == 2:
if x is None:
x = np.zeros((1,2))
else:
x = np.asarray(x)
assert x.size == 2, "The size of the fixed variable x is not 2"
x = x.reshape((1,2))
if plot_limits == None:
xmin, xmax = (x-5).flatten(), (x+5).flatten()
elif len(plot_limits) == 2:
xmin, xmax = plot_limits
else:
raise ValueError, "Bad limits for plotting"
resolution = resolution or 51
xx,yy = np.mgrid[xmin[0]:xmax[0]:1j*resolution,xmin[1]:xmax[1]:1j*resolution]
xg = np.linspace(xmin[0],xmax[0],resolution)
yg = np.linspace(xmin[1],xmax[1],resolution)
Xnew = np.vstack((xx.flatten(),yy.flatten())).T
Kx = self.K(Xnew,x,slices2=which_functions)
Kx = Kx.reshape(resolution,resolution).T
pb.contour(xg,yg,Kx,vmin=Kx.min(),vmax=Kx.max(),cmap=pb.cm.jet)
pb.xlim(xmin[0],xmax[0])
pb.ylim(xmin[1],xmax[1])
pb.xlabel("x1")
pb.ylabel("x2")
pb.title("k(x1,x2 ; %0.1f,%0.1f)" %(x[0,0],x[0,1]) )
else:
raise NotImplementedError, "Cannot plot a kernel with more than two input dimensions"

View file

@ -15,8 +15,8 @@ class linear(kernpart):
:param D: the number of input dimensions :param D: the number of input dimensions
:type D: int :type D: int
:param variances: the vector of variances :math:`\sigma^2_i` :param variances: the vector of variances :math:`\sigma^2_i`
:type variances: np.ndarray of size (1,) or (D,) depending on ARD :type variances: array or list of the appropriate size (or float if there is only one variance parameter)
:param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single variance parameter \sigma^2), otherwise there is one variance parameter per dimension. :param ARD: Auto Relevance Determination. If equal to "False", the kernel has only one variance parameter \sigma^2, otherwise there is one variance parameter per dimension.
:type ARD: Boolean :type ARD: Boolean
:rtype: kernel object :rtype: kernel object
""" """
@ -28,21 +28,20 @@ class linear(kernpart):
self.Nparam = 1 self.Nparam = 1
self.name = 'linear' self.name = 'linear'
if variances is not None: if variances is not None:
if isinstance(variances, float): variances = np.asarray(variances)
variances = np.array([variances]) assert variances.size == 1, "Only one variance needed for non-ARD kernel"
assert variances.shape == (1,)
else: else:
variances = np.ones(1) variances = np.ones(1)
self._Xcache, self._X2cache = np.empty(shape=(2,)) self._Xcache, self._X2cache = np.empty(shape=(2,))
else: else:
self.Nparam = self.D self.Nparam = self.D
self.name = 'linear_ARD' self.name = 'linear'
if variances is not None: if variances is not None:
assert variances.shape == (self.D,) variances = np.asarray(variances)
assert variances.size == self.D, "bad number of lengthscales"
else: else:
variances = np.ones(self.D) variances = np.ones(self.D)
self._set_params(variances) self._set_params(variances.flatten())
def _get_params(self): def _get_params(self):
return self.variances return self.variances

View file

@ -12,7 +12,7 @@ class rbf(kernpart):
.. math:: .. math::
k(r) = \sigma^2 \exp(- \frac{1}{2}r^2) \qquad \qquad \\text{ where } r^2 = \sum_{i=1}^d \frac{ (x_i-x^\prime_i)^2}{\ell_i^2}} k(r) = \sigma^2 \exp(- \frac{1}{2}r^2) \ \ \ \ \ \\text{ where } r^2 = \sum_{i=1}^d \frac{ (x_i-x^\prime_i)^2}{\ell_i^2}}
where \ell_i is the lengthscale, \sigma^2 the variance and d the dimensionality of the input. where \ell_i is the lengthscale, \sigma^2 the variance and d the dimensionality of the input.
@ -21,7 +21,7 @@ class rbf(kernpart):
:param variance: the variance of the kernel :param variance: the variance of the kernel
:type variance: float :type variance: float
:param lengthscale: the vector of lengthscale of the kernel :param lengthscale: the vector of lengthscale of the kernel
:type lengthscale: np.ndarray od size (1,) or (D,) depending on ARD :type lengthscale: array or list of the appropriate size (or float if there is only one lengthscale parameter)
:param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension. :param ARD: Auto Relevance Determination. If equal to "False", the kernel is isotropic (ie. one single lengthscale parameter \ell), otherwise there is one lengthscale parameter per dimension.
:type ARD: Boolean :type ARD: Boolean
:rtype: kernel object :rtype: kernel object

311
GPy/likelihoods/EP.py Normal file
View file

@ -0,0 +1,311 @@
import numpy as np
from scipy import stats, linalg
from ..util.linalg import pdinv,mdot,jitchol
from likelihood import likelihood
class EP(likelihood):
def __init__(self,data,likelihood_function,epsilon=1e-3,power_ep=[1.,1.]):
"""
Expectation Propagation
Arguments
---------
epsilon : Convergence criterion, maximum squared difference allowed between mean updates to stop iterations (float)
likelihood_function : a likelihood function (see likelihood_functions.py)
"""
self.likelihood_function = likelihood_function
self.epsilon = epsilon
self.eta, self.delta = power_ep
self.data = data
self.N = self.data.size
self.is_heteroscedastic = True
self.Nparams = 0
#Initial values - Likelihood approximation parameters:
#p(y|f) = t(f|tau_tilde,v_tilde)
self.tau_tilde = np.zeros(self.N)
self.v_tilde = np.zeros(self.N)
#initial values for the GP variables
self.Y = np.zeros((self.N,1))
self.covariance_matrix = np.eye(self.N)
self.precision = np.ones(self.N)
self.Z = 0
self.YYT = None
def predictive_values(self,mu,var):
return self.likelihood_function.predictive_values(mu,var)
def _get_params(self):
return np.zeros(0)
def _get_param_names(self):
return []
def _set_params(self,p):
pass # TODO: the EP likelihood might want to take some parameters...
def _gradients(self,partial):
return np.zeros(0) # TODO: the EP likelihood might want to take some parameters...
def _compute_GP_variables(self):
#Variables to be called from GP
mu_tilde = self.v_tilde/self.tau_tilde #When calling EP, this variable is used instead of Y in the GP model
sigma_sum = 1./self.tau_ + 1./self.tau_tilde
mu_diff_2 = (self.v_/self.tau_ - mu_tilde)**2
self.Z = np.sum(np.log(self.Z_hat)) + 0.5*np.sum(np.log(sigma_sum)) + 0.5*np.sum(mu_diff_2/sigma_sum) #Normalization constant, aka Z_ep
self.Y = mu_tilde[:,None]
self.YYT = np.dot(self.Y,self.Y.T)
self.precision = self.tau_tilde
self.covariance_matrix = np.diag(1./self.precision)
def fit_full(self,K):
"""
The expectation-propagation algorithm.
For nomenclature see Rasmussen & Williams 2006.
"""
#Prior distribution parameters: p(f|X) = N(f|0,K)
self.tau_tilde = np.zeros(self.N)
self.v_tilde = np.zeros(self.N)
#Initial values - Posterior distribution parameters: q(f|X,Y) = N(f|mu,Sigma)
mu = np.zeros(self.N)
Sigma = K.copy()
"""
Initial values - Cavity distribution parameters:
q_(f|mu_,sigma2_) = Product{q_i(f|mu_i,sigma2_i)}
sigma_ = 1./tau_
mu_ = v_/tau_
"""
self.tau_ = np.empty(self.N,dtype=float)
self.v_ = np.empty(self.N,dtype=float)
#Initial values - Marginal moments
z = np.empty(self.N,dtype=float)
self.Z_hat = np.empty(self.N,dtype=float)
phi = np.empty(self.N,dtype=float)
mu_hat = np.empty(self.N,dtype=float)
sigma2_hat = np.empty(self.N,dtype=float)
#Approximation
epsilon_np1 = self.epsilon + 1.
epsilon_np2 = self.epsilon + 1.
self.iterations = 0
self.np1 = [self.tau_tilde.copy()]
self.np2 = [self.v_tilde.copy()]
while epsilon_np1 > self.epsilon or epsilon_np2 > self.epsilon:
update_order = np.random.permutation(self.N)
for i in update_order:
#Cavity distribution parameters
self.tau_[i] = 1./Sigma[i,i] - self.eta*self.tau_tilde[i]
self.v_[i] = mu[i]/Sigma[i,i] - self.eta*self.v_tilde[i]
#Marginal moments
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.likelihood_function.moments_match(self.data[i],self.tau_[i],self.v_[i])
#Site parameters update
Delta_tau = self.delta/self.eta*(1./sigma2_hat[i] - 1./Sigma[i,i])
Delta_v = self.delta/self.eta*(mu_hat[i]/sigma2_hat[i] - mu[i]/Sigma[i,i])
self.tau_tilde[i] = self.tau_tilde[i] + Delta_tau
self.v_tilde[i] = self.v_tilde[i] + Delta_v
#Posterior distribution parameters update
si=Sigma[:,i].reshape(self.N,1)
Sigma = Sigma - Delta_tau/(1.+ Delta_tau*Sigma[i,i])*np.dot(si,si.T)
mu = np.dot(Sigma,self.v_tilde)
self.iterations += 1
#Sigma recomptutation with Cholesky decompositon
Sroot_tilde_K = np.sqrt(self.tau_tilde)[:,None]*K
B = np.eye(self.N) + np.sqrt(self.tau_tilde)[None,:]*Sroot_tilde_K
L = jitchol(B)
V,info = linalg.flapack.dtrtrs(L,Sroot_tilde_K,lower=1)
Sigma = K - np.dot(V.T,V)
mu = np.dot(Sigma,self.v_tilde)
epsilon_np1 = sum((self.tau_tilde-self.np1[-1])**2)/self.N
epsilon_np2 = sum((self.v_tilde-self.np2[-1])**2)/self.N
self.np1.append(self.tau_tilde.copy())
self.np2.append(self.v_tilde.copy())
return self._compute_GP_variables()
def fit_DTC(self, Knn_diag, Kmn, Kmm):
"""
The expectation-propagation algorithm with sparse pseudo-input.
For nomenclature see ... 2013.
"""
#TODO: this doesn;t work with uncertain inputs!
"""
Prior approximation parameters:
q(f|X) = int_{df}{N(f|KfuKuu_invu,diag(Kff-Qff)*N(u|0,Kuu)} = N(f|0,Sigma0)
Sigma0 = Qnn = Knm*Kmmi*Kmn
"""
Kmmi, Lm, Lmi, Kmm_logdet = pdinv(Kmm)
KmnKnm = np.dot(Kmn, Kmn.T)
KmmiKmn = np.dot(Kmmi,Kmn)
Qnn_diag = np.sum(Kmn*KmmiKmn,-2)
LLT0 = Kmm.copy()
"""
Posterior approximation: q(f|y) = N(f| mu, Sigma)
Sigma = Diag + P*R.T*R*P.T + K
mu = w + P*gamma
"""
mu = np.zeros(self.N)
LLT = Kmm.copy()
Sigma_diag = Qnn_diag.copy()
"""
Initial values - Cavity distribution parameters:
q_(g|mu_,sigma2_) = Product{q_i(g|mu_i,sigma2_i)}
sigma_ = 1./tau_
mu_ = v_/tau_
"""
tau_ = np.empty(self.N,dtype=float)
v_ = np.empty(self.N,dtype=float)
#Initial values - Marginal moments
z = np.empty(self.N,dtype=float)
Z_hat = np.empty(self.N,dtype=float)
phi = np.empty(self.N,dtype=float)
mu_hat = np.empty(self.N,dtype=float)
sigma2_hat = np.empty(self.N,dtype=float)
#Approximation
epsilon_np1 = 1
epsilon_np2 = 1
self.iterations = 0
np1 = [tau_tilde.copy()]
np2 = [v_tilde.copy()]
while epsilon_np1 > self.epsilon or epsilon_np2 > self.epsilon:
update_order = np.random.permutation(self.N)
for i in update_order:
#Cavity distribution parameters
tau_[i] = 1./Sigma_diag[i] - self.eta*tau_tilde[i]
v_[i] = mu[i]/Sigma_diag[i] - self.eta*v_tilde[i]
#Marginal moments
Z_hat[i], mu_hat[i], sigma2_hat[i] = self.likelihood_function.moments_match(self.data[i],tau_[i],v_[i])
#Site parameters update
Delta_tau = delta/self.eta*(1./sigma2_hat[i] - 1./Sigma_diag[i])
Delta_v = self.delta/self.eta*(mu_hat[i]/sigma2_hat[i] - mu[i]/Sigma_diag[i])
tau_tilde[i] = tau_tilde[i] + Delta_tau
v_tilde[i] = v_tilde[i] + Delta_v
#Posterior distribution parameters update
LLT = LLT + np.outer(Kmn[:,i],Kmn[:,i])*Delta_tau
L = jitchol(LLT)
V,info = linalg.flapack.dtrtrs(L,Kmn,lower=1)
Sigma_diag = np.sum(V*V,-2)
si = np.sum(V.T*V[:,i],-1)
mu = mu + (Delta_v-Delta_tau*mu[i])*si
self.iterations += 1
#Sigma recomputation with Cholesky decompositon
LLT0 = LLT0 + np.dot(Kmn*tau_tilde[None,:],Kmn.T)
L = jitchol(LLT)
V,info = linalg.flapack.dtrtrs(L,Kmn,lower=1)
V2,info = linalg.flapack.dtrtrs(L.T,V,lower=0)
Sigma_diag = np.sum(V*V,-2)
Knmv_tilde = np.dot(Kmn,v_tilde)
mu = np.dot(V2.T,Knmv_tilde)
epsilon_np1 = sum((tau_tilde-np1[-1])**2)/self.N
epsilon_np2 = sum((v_tilde-np2[-1])**2)/self.N
np1.append(tau_tilde.copy())
np2.append(v_tilde.copy())
self._compute_GP_variables()
def fit_FITC(self, Knn_diag, Kmn):
"""
The expectation-propagation algorithm with sparse pseudo-input.
For nomenclature see Naish-Guzman and Holden, 2008.
"""
"""
Prior approximation parameters:
q(f|X) = int_{df}{N(f|KfuKuu_invu,diag(Kff-Qff)*N(u|0,Kuu)} = N(f|0,Sigma0)
Sigma0 = diag(Knn-Qnn) + Qnn, Qnn = Knm*Kmmi*Kmn
"""
Kmmi, self.Lm, self.Lmi, Kmm_logdet = pdinv(Kmm)
P0 = Kmn.T
KmnKnm = np.dot(P0.T, P0)
KmmiKmn = np.dot(Kmmi,P0.T)
Qnn_diag = np.sum(P0.T*KmmiKmn,-2)
Diag0 = Knn_diag - Qnn_diag
R0 = jitchol(Kmmi).T
"""
Posterior approximation: q(f|y) = N(f| mu, Sigma)
Sigma = Diag + P*R.T*R*P.T + K
mu = w + P*gamma
"""
self.w = np.zeros(self.N)
self.gamma = np.zeros(self.M)
mu = np.zeros(self.N)
P = P0.copy()
R = R0.copy()
Diag = Diag0.copy()
Sigma_diag = Knn_diag
"""
Initial values - Cavity distribution parameters:
q_(g|mu_,sigma2_) = Product{q_i(g|mu_i,sigma2_i)}
sigma_ = 1./tau_
mu_ = v_/tau_
"""
self.tau_ = np.empty(self.N,dtype=float)
self.v_ = np.empty(self.N,dtype=float)
#Initial values - Marginal moments
z = np.empty(self.N,dtype=float)
self.Z_hat = np.empty(self.N,dtype=float)
phi = np.empty(self.N,dtype=float)
mu_hat = np.empty(self.N,dtype=float)
sigma2_hat = np.empty(self.N,dtype=float)
#Approximation
epsilon_np1 = 1
epsilon_np2 = 1
self.iterations = 0
self.np1 = [self.tau_tilde.copy()]
self.np2 = [self.v_tilde.copy()]
while epsilon_np1 > self.epsilon or epsilon_np2 > self.epsilon:
update_order = np.random.permutation(self.N)
for i in update_order:
#Cavity distribution parameters
self.tau_[i] = 1./Sigma_diag[i] - self.eta*self.tau_tilde[i]
self.v_[i] = mu[i]/Sigma_diag[i] - self.eta*self.v_tilde[i]
#Marginal moments
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.likelihood_function.moments_match(data[i],self.tau_[i],self.v_[i])
#Site parameters update
Delta_tau = self.delta/self.eta*(1./sigma2_hat[i] - 1./Sigma_diag[i])
Delta_v = self.delta/self.eta*(mu_hat[i]/sigma2_hat[i] - mu[i]/Sigma_diag[i])
self.tau_tilde[i] = self.tau_tilde[i] + Delta_tau
self.v_tilde[i] = self.v_tilde[i] + Delta_v
#Posterior distribution parameters update
dtd1 = Delta_tau*Diag[i] + 1.
dii = Diag[i]
Diag[i] = dii - (Delta_tau * dii**2.)/dtd1
pi_ = P[i,:].reshape(1,self.M)
P[i,:] = pi_ - (Delta_tau*dii)/dtd1 * pi_
Rp_i = np.dot(R,pi_.T)
RTR = np.dot(R.T,np.dot(np.eye(self.M) - Delta_tau/(1.+Delta_tau*Sigma_diag[i]) * np.dot(Rp_i,Rp_i.T),R))
R = jitchol(RTR).T
self.w[i] = self.w[i] + (Delta_v - Delta_tau*self.w[i])*dii/dtd1
self.gamma = self.gamma + (Delta_v - Delta_tau*mu[i])*np.dot(RTR,P[i,:].T)
RPT = np.dot(R,P.T)
Sigma_diag = Diag + np.sum(RPT.T*RPT.T,-1)
mu = self.w + np.dot(P,self.gamma)
self.iterations += 1
#Sigma recomptutation with Cholesky decompositon
Diag = Diag0/(1.+ Diag0 * self.tau_tilde)
P = (Diag / Diag0)[:,None] * P0
RPT0 = np.dot(R0,P0.T)
L = jitchol(np.eye(self.M) + np.dot(RPT0,(1./Diag0 - Diag/(Diag0**2))[:,None]*RPT0.T))
R,info = linalg.flapack.dtrtrs(L,R0,lower=1)
RPT = np.dot(R,P.T)
Sigma_diag = Diag + np.sum(RPT.T*RPT.T,-1)
self.w = Diag * self.v_tilde
self.gamma = np.dot(R.T, np.dot(RPT,self.v_tilde))
mu = self.w + np.dot(P,self.gamma)
epsilon_np1 = sum((self.tau_tilde-self.np1[-1])**2)/self.N
epsilon_np2 = sum((self.v_tilde-self.np2[-1])**2)/self.N
self.np1.append(self.tau_tilde.copy())
self.np2.append(self.v_tilde.copy())
return self._compute_GP_variables()

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@ -0,0 +1,56 @@
import numpy as np
from likelihood import likelihood
class Gaussian(likelihood):
def __init__(self,data,variance=1.,normalize=False):
self.is_heteroscedastic = False
self.Nparams = 1
self.data = data
self.N,D = data.shape
self.Z = 0. # a correction factor which accounts for the approximation made
#normalisation
if normalize:
self._mean = data.mean(0)[None,:]
self._std = data.std(0)[None,:]
self.Y = (self.data - self._mean)/self._std
else:
self._mean = np.zeros((1,D))
self._std = np.ones((1,D))
self.Y = self.data
#TODO: make this work efficiently (only compute YYT if D>>N)
self.YYT = np.dot(self.Y,self.Y.T)
self.trYYT = np.trace(self.YYT)
self._set_params(np.asarray(variance))
def _get_params(self):
return np.asarray(self._variance)
def _get_param_names(self):
return ["noise variance"]
def _set_params(self,x):
self._variance = float(x)
self.covariance_matrix = np.eye(self.N)*self._variance
self.precision = 1./self._variance
def predictive_values(self,mu,var):
"""
Un-normalise the prediction and add the likelihood variance, then return the 5%, 95% interval
"""
mean = mu*self._std + self._mean
true_var = (var + self._variance)*self._std**2
_5pc = mean + - 2.*np.sqrt(true_var)
_95pc = mean + 2.*np.sqrt(true_var)
return mean, _5pc, _95pc
def fit_full(self):
"""
No approximations needed
"""
pass
def _gradients(self,partial):
return np.sum(partial)

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@ -0,0 +1,4 @@
from EP import EP
from Gaussian import Gaussian
# TODO: from Laplace import Laplace
import likelihood_functions as functions

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@ -0,0 +1,35 @@
import numpy as np
class likelihood:
"""
The atom for a likelihood class
This object interfaces the GP and the data. The most basic likelihood
(Gaussian) inherits directly from this, as does the EP algorithm
Some things must be defined for this to work properly:
self.Y : the effective Gaussian target of the GP
self.N, self.D : Y.shape
self.covariance_matrix : the effective (noise) covariance of the GP targets
self.Z : a factor which gets added to the likelihood (0 for a Gaussian, Z_EP for EP)
self.is_heteroscedastic : enables significant computational savings in GP
self.precision : a scalar or vector representation of the effective target precision
self.YYT : (optional) = np.dot(self.Y, self.Y.T) enables computational savings for D>N
"""
def __init__(self,data):
raise ValueError, "this class is not to be instantiated"
def _get_params(self):
raise NotImplementedError
def _get_param_names(self):
raise NotImplementedError
def _set_params(self,x):
raise NotImplementedError
def fit(self):
raise NotImplementedError
def _gradients(self,partial):
raise NotImplementedError

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@ -0,0 +1,134 @@
# Copyright (c) 2012, 2013 Ricardo Andrade
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
from scipy import stats
import scipy as sp
import pylab as pb
from ..util.plot import gpplot
class likelihood_function:
"""
Likelihood class for doing Expectation propagation
:param Y: observed output (Nx1 numpy.darray)
..Note:: Y values allowed depend on the likelihood_function used
"""
def __init__(self,location=0,scale=1):
self.location = location
self.scale = scale
class probit(likelihood_function):
"""
Probit likelihood
Y is expected to take values in {-1,1}
-----
$$
L(x) = \\Phi (Y_i*f_i)
$$
"""
def moments_match(self,data_i,tau_i,v_i):
"""
Moments match of the marginal approximation in EP algorithm
:param i: number of observation (int)
:param tau_i: precision of the cavity distribution (float)
:param v_i: mean/variance of the cavity distribution (float)
"""
# TODO: some version of assert np.sum(np.abs(Y)-1) == 0, "Output values must be either -1 or 1"
if data_i == 0: data_i = -1 #NOTE Binary classification works better classes {-1,1}, 1D-plotting works better with classes {0,1}.
z = data_i*v_i/np.sqrt(tau_i**2 + tau_i)
Z_hat = stats.norm.cdf(z)
phi = stats.norm.pdf(z)
mu_hat = v_i/tau_i + data_i*phi/(Z_hat*np.sqrt(tau_i**2 + tau_i))
sigma2_hat = 1./tau_i - (phi/((tau_i**2+tau_i)*Z_hat))*(z+phi/Z_hat)
return Z_hat, mu_hat, sigma2_hat
def predictive_values(self,mu,var):
"""
Compute mean, and conficence interval (percentiles 5 and 95) of the prediction
"""
mu = mu.flatten()
var = var.flatten()
mean = stats.norm.cdf(mu/np.sqrt(1+var))
p_025 = np.zeros(mu.shape)
p_975 = np.ones(mu.shape)
return mean, p_025, p_975
class Poisson(likelihood_function):
"""
Poisson likelihood
Y is expected to take values in {0,1,2,...}
-----
$$
L(x) = \exp(\lambda) * \lambda**Y_i / Y_i!
$$
"""
def moments_match(self,data_i,tau_i,v_i):
"""
Moments match of the marginal approximation in EP algorithm
:param i: number of observation (int)
:param tau_i: precision of the cavity distribution (float)
:param v_i: mean/variance of the cavity distribution (float)
"""
mu = v_i/tau_i
sigma = np.sqrt(1./tau_i)
def poisson_norm(f):
"""
Product of the likelihood and the cavity distribution
"""
pdf_norm_f = stats.norm.pdf(f,loc=mu,scale=sigma)
rate = np.exp( (f*self.scale)+self.location)
poisson = stats.poisson.pmf(float(data_i),rate)
return pdf_norm_f*poisson
def log_pnm(f):
"""
Log of poisson_norm
"""
return -(-.5*(f-mu)**2/sigma**2 - np.exp( (f*self.scale)+self.location) + ( (f*self.scale)+self.location)*data_i)
"""
Golden Search and Simpson's Rule
--------------------------------
Simpson's Rule is used to calculate the moments mumerically, it needs a grid of points as input.
Golden Search is used to find the mode in the poisson_norm distribution and define around it the grid for Simpson's Rule
"""
#TODO golden search & simpson's rule can be defined in the general likelihood class, rather than in each specific case.
#Golden search
golden_A = -1 if data_i == 0 else np.array([np.log(data_i),mu]).min() #Lower limit
golden_B = np.array([np.log(data_i),mu]).max() #Upper limit
golden_A = (golden_A - self.location)/self.scale
golden_B = (golden_B - self.location)/self.scale
opt = sp.optimize.golden(log_pnm,brack=(golden_A,golden_B)) #Better to work with log_pnm than with poisson_norm
# Simpson's approximation
width = 3./np.log(max(data_i,2))
A = opt - width #Lower limit
B = opt + width #Upper limit
K = 10*int(np.log(max(data_i,150))) #Number of points in the grid, we DON'T want K to be the same number for every case
h = (B-A)/K # length of the intervals
grid_x = np.hstack([np.linspace(opt-width,opt,K/2+1)[1:-1], np.linspace(opt,opt+width,K/2+1)]) # grid of points (X axis)
x = np.hstack([A,B,grid_x[range(1,K,2)],grid_x[range(2,K-1,2)]]) # grid_x rearranged, just to make Simpson's algorithm easier
zeroth = np.hstack([poisson_norm(A),poisson_norm(B),[4*poisson_norm(f) for f in grid_x[range(1,K,2)]],[2*poisson_norm(f) for f in grid_x[range(2,K-1,2)]]]) # grid of points (Y axis) rearranged like x
first = zeroth*x
second = first*x
Z_hat = sum(zeroth)*h/3 # Zero-th moment
mu_hat = sum(first)*h/(3*Z_hat) # First moment
m2 = sum(second)*h/(3*Z_hat) # Second moment
sigma2_hat = m2 - mu_hat**2 # Second central moment
return float(Z_hat), float(mu_hat), float(sigma2_hat)
def predictive_values(self,mu,var):
"""
Compute mean, and conficence interval (percentiles 5 and 95) of the prediction
"""
mean = np.exp(mu*self.scale + self.location)
tmp = stats.poisson.ppf(np.array([.025,.975]),mean)
p_025 = tmp[:,0]
p_975 = tmp[:,1]
return mean,p_025,p_975

View file

@ -5,10 +5,12 @@ import numpy as np
import pylab as pb import pylab as pb
import sys, pdb import sys, pdb
from GPLVM import GPLVM from GPLVM import GPLVM
from sparse_GP_regression import sparse_GP_regression from sparse_GP import sparse_GP
from GPy.util.linalg import pdinv from GPy.util.linalg import pdinv
from ..likelihoods import Gaussian
from .. import kern
class Bayesian_GPLVM(sparse_GP_regression, GPLVM): class Bayesian_GPLVM(sparse_GP, GPLVM):
""" """
Bayesian Gaussian Process Latent Variable Model Bayesian Gaussian Process Latent Variable Model
@ -20,15 +22,23 @@ class Bayesian_GPLVM(sparse_GP_regression, GPLVM):
:type init: 'PCA'|'random' :type init: 'PCA'|'random'
""" """
def __init__(self, Y, Q, init='PCA', **kwargs): def __init__(self, Y, Q, init='PCA', M=10, Z=None, **kwargs):
X = self.initialise_latent(init, Q, Y) X = self.initialise_latent(init, Q, Y)
S = np.ones_like(X) * 1e-2#
sparse_GP_regression.__init__(self, X, Y, X_uncertainty = S, **kwargs) if Z is None:
Z = np.random.permutation(X.copy())[:M]
else:
assert Z.shape[1]==X.shape[1]
kernel = kern.rbf(Q) + kern.white(Q)
S = np.ones_like(X) * 1e-2#
sparse_GP.__init__(self, X, Gaussian(Y), X_uncertainty=S, Z=Z,**kwargs)
def _get_param_names(self): def _get_param_names(self):
X_names = sum([['X_%i_%i'%(n,q) for n in range(self.N)] for q in range(self.Q)],[]) X_names = sum([['X_%i_%i'%(n,q) for n in range(self.N)] for q in range(self.Q)],[])
S_names = sum([['S_%i_%i'%(n,q) for n in range(self.N)] for q in range(self.Q)],[]) S_names = sum([['S_%i_%i'%(n,q) for n in range(self.N)] for q in range(self.Q)],[])
return (X_names + S_names + sparse_GP_regression._get_param_names(self)) return (X_names + S_names + sparse_GP._get_param_names(self))
def _get_params(self): def _get_params(self):
""" """
@ -36,17 +46,17 @@ class Bayesian_GPLVM(sparse_GP_regression, GPLVM):
The resulting 1-D array has this structure: The resulting 1-D array has this structure:
=============================================================== ===============================================================
| mu | S | Z | beta | theta | | mu | S | Z | theta | beta |
=============================================================== ===============================================================
""" """
return np.hstack((self.X.flatten(), self.X_uncertainty.flatten(), sparse_GP_regression._get_params(self))) return np.hstack((self.X.flatten(), self.X_uncertainty.flatten(), sparse_GP._get_params(self)))
def _set_params(self,x): def _set_params(self,x):
N, Q = self.N, self.Q N, Q = self.N, self.Q
self.X = x[:self.X.size].reshape(N,Q).copy() self.X = x[:self.X.size].reshape(N,Q).copy()
self.X_uncertainty = x[(N*Q):(2*N*Q)].reshape(N,Q).copy() self.X_uncertainty = x[(N*Q):(2*N*Q)].reshape(N,Q).copy()
sparse_GP_regression._set_params(self, x[(2*N*Q):]) sparse_GP._set_params(self, x[(2*N*Q):])
def dL_dmuS(self): def dL_dmuS(self):
dL_dmu_psi0, dL_dS_psi0 = self.kern.dpsi1_dmuS(self.dL_dpsi1,self.Z,self.X,self.X_uncertainty) dL_dmu_psi0, dL_dS_psi0 = self.kern.dpsi1_dmuS(self.dL_dpsi1,self.Z,self.X,self.X_uncertainty)
@ -58,5 +68,5 @@ class Bayesian_GPLVM(sparse_GP_regression, GPLVM):
return np.hstack((dL_dmu.flatten(), dL_dS.flatten())) return np.hstack((dL_dmu.flatten(), dL_dS.flatten()))
def _log_likelihood_gradients(self): def _log_likelihood_gradients(self):
return np.hstack((self.dL_dmuS().flatten(), sparse_GP_regression._log_likelihood_gradients(self))) return np.hstack((self.dL_dmuS().flatten(), sparse_GP._log_likelihood_gradients(self)))

274
GPy/models/GP.py Normal file
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@ -0,0 +1,274 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
import pylab as pb
from .. import kern
from ..core import model
from ..util.linalg import pdinv,mdot
from ..util.plot import gpplot,x_frame1D,x_frame2D, Tango
from ..likelihoods import EP
class GP(model):
"""
Gaussian Process model for regression and EP
:param X: input observations
:param kernel: a GPy kernel, defaults to rbf+white
:parm likelihood: a GPy likelihood
:param normalize_X: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_X: False|True
:param normalize_Y: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_Y: False|True
:param Xslices: how the X,Y data co-vary in the kernel (i.e. which "outputs" they correspond to). See (link:slicing)
:rtype: model object
:param epsilon_ep: convergence criterion for the Expectation Propagation algorithm, defaults to 0.1
:param powerep: power-EP parameters [$\eta$,$\delta$], defaults to [1.,1.]
:type powerep: list
.. Note:: Multiple independent outputs are allowed using columns of Y
"""
#FIXME normalize vs normalise
def __init__(self, X, likelihood, kernel, normalize_X=False, Xslices=None):
# parse arguments
self.Xslices = Xslices
self.X = X
assert len(self.X.shape)==2
self.N, self.Q = self.X.shape
assert isinstance(kernel, kern.kern)
self.kern = kernel
#here's some simple normalisation for the inputs
if normalize_X:
self._Xmean = X.mean(0)[None,:]
self._Xstd = X.std(0)[None,:]
self.X = (X.copy() - self._Xmean) / self._Xstd
if hasattr(self,'Z'):
self.Z = (self.Z - self._Xmean) / self._Xstd
else:
self._Xmean = np.zeros((1,self.X.shape[1]))
self._Xstd = np.ones((1,self.X.shape[1]))
self.likelihood = likelihood
#assert self.X.shape[0] == self.likelihood.Y.shape[0]
#self.N, self.D = self.likelihood.Y.shape
assert self.X.shape[0] == self.likelihood.data.shape[0]
self.N, self.D = self.likelihood.data.shape
model.__init__(self)
def _set_params(self,p):
self.kern._set_params_transformed(p[:self.kern.Nparam])
#self.likelihood._set_params(p[self.kern.Nparam:]) # test by Nicolas
self.likelihood._set_params(p[self.kern.Nparam_transformed():]) # test by Nicolas
self.K = self.kern.K(self.X,slices1=self.Xslices)
self.K += self.likelihood.covariance_matrix
self.Ki, self.L, self.Li, self.K_logdet = pdinv(self.K)
#the gradient of the likelihood wrt the covariance matrix
if self.likelihood.YYT is None:
alpha = np.dot(self.Ki,self.likelihood.Y)
self.dL_dK = 0.5*(np.dot(alpha,alpha.T)-self.D*self.Ki)
else:
tmp = mdot(self.Ki, self.likelihood.YYT, self.Ki)
self.dL_dK = 0.5*(tmp - self.D*self.Ki)
def _get_params(self):
return np.hstack((self.kern._get_params_transformed(), self.likelihood._get_params()))
def _get_param_names(self):
return self.kern._get_param_names_transformed() + self.likelihood._get_param_names()
def update_likelihood_approximation(self):
"""
Approximates a non-gaussian likelihood using Expectation Propagation
For a Gaussian (or direct: TODO) likelihood, no iteration is required:
this function does nothing
"""
self.likelihood.fit_full(self.kern.K(self.X))
self._set_params(self._get_params()) # update the GP
def _model_fit_term(self):
"""
Computes the model fit using YYT if it's available
"""
if self.likelihood.YYT is None:
return -0.5*np.sum(np.square(np.dot(self.Li,self.likelihood.Y)))
else:
return -0.5*np.sum(np.multiply(self.Ki, self.likelihood.YYT))
def log_likelihood(self):
"""
The log marginal likelihood of the GP.
For an EP model, can be written as the log likelihood of a regression
model for a new variable Y* = v_tilde/tau_tilde, with a covariance
matrix K* = K + diag(1./tau_tilde) plus a normalization term.
"""
return -0.5*self.D*self.K_logdet + self._model_fit_term() + self.likelihood.Z
def _log_likelihood_gradients(self):
"""
The gradient of all parameters.
For the kernel parameters, use the chain rule via dL_dK
For the likelihood parameters, pass in alpha = K^-1 y
"""
return np.hstack((self.kern.dK_dtheta(partial=self.dL_dK,X=self.X), self.likelihood._gradients(partial=np.diag(self.dL_dK))))
def _raw_predict(self,_Xnew,slices=None, full_cov=False):
"""
Internal helper function for making predictions, does not account
for normalisation or likelihood
"""
Kx = self.kern.K(self.X,_Xnew, slices1=self.Xslices,slices2=slices)
mu = np.dot(np.dot(Kx.T,self.Ki),self.likelihood.Y)
KiKx = np.dot(self.Ki,Kx)
if full_cov:
Kxx = self.kern.K(_Xnew, slices1=slices,slices2=slices)
var = Kxx - np.dot(KiKx.T,Kx) #NOTE this won't work for plotting
else:
Kxx = self.kern.Kdiag(_Xnew, slices=slices)
var = Kxx - np.sum(np.multiply(KiKx,Kx),0)
var = var[:,None]
return mu, var
def predict(self,Xnew, slices=None, full_cov=False):
"""
Predict the function(s) at the new point(s) Xnew.
Arguments
---------
:param Xnew: The points at which to make a prediction
:type Xnew: np.ndarray, Nnew x self.Q
:param slices: specifies which outputs kernel(s) the Xnew correspond to (see below)
:type slices: (None, list of slice objects, list of ints)
:param full_cov: whether to return the folll covariance matrix, or just the diagonal
:type full_cov: bool
:rtype: posterior mean, a Numpy array, Nnew x self.D
:rtype: posterior variance, a Numpy array, Nnew x 1 if full_cov=False, Nnew x Nnew otherwise
:rtype: lower and upper boundaries of the 95% confidence intervals, Numpy arrays, Nnew x self.D
.. Note:: "slices" specifies how the the points X_new co-vary wich the training points.
- If None, the new points covary throigh every kernel part (default)
- If a list of slices, the i^th slice specifies which data are affected by the i^th kernel part
- If a list of booleans, specifying which kernel parts are active
If full_cov and self.D > 1, the return shape of var is Nnew x Nnew x self.D. If self.D == 1, the return shape is Nnew x Nnew.
This is to allow for different normalisations of the output dimensions.
"""
#normalise X values
Xnew = (Xnew.copy() - self._Xmean) / self._Xstd
mu, var = self._raw_predict(Xnew, slices, full_cov)
#now push through likelihood TODO
mean, _025pm, _975pm = self.likelihood.predictive_values(mu, var)
return mean, var, _025pm, _975pm
def plot_f(self, samples=0, plot_limits=None, which_data='all', which_functions='all', resolution=None, full_cov=False):
"""
Plot the GP's view of the world, where the data is normalised and the likelihood is Gaussian
:param samples: the number of a posteriori samples to plot
:param which_data: which if the training data to plot (default all)
:type which_data: 'all' or a slice object to slice self.X, self.Y
:param plot_limits: The limits of the plot. If 1D [xmin,xmax], if 2D [[xmin,ymin],[xmax,ymax]]. Defaluts to data limits
:param which_functions: which of the kernel functions to plot (additively)
:type which_functions: list of bools
:param resolution: the number of intervals to sample the GP on. Defaults to 200 in 1D and 50 (a 50x50 grid) in 2D
Plot the posterior of the GP.
- In one dimension, the function is plotted with a shaded region identifying two standard deviations.
- In two dimsensions, a contour-plot shows the mean predicted function
- In higher dimensions, we've no implemented this yet !TODO!
Can plot only part of the data and part of the posterior functions using which_data and which_functions
Plot the data's view of the world, with non-normalised values and GP predictions passed through the likelihood
"""
if which_functions=='all':
which_functions = [True]*self.kern.Nparts
if which_data=='all':
which_data = slice(None)
if self.X.shape[1] == 1:
Xnew, xmin, xmax = x_frame1D(self.X, plot_limits=plot_limits)
if samples == 0:
m,v = self._raw_predict(Xnew, slices=which_functions)
gpplot(Xnew,m,m-2*np.sqrt(v),m+2*np.sqrt(v))
pb.plot(self.X[which_data],self.likelihood.Y[which_data],'kx',mew=1.5)
else:
m,v = self._raw_predict(Xnew, slices=which_functions,full_cov=True)
Ysim = np.random.multivariate_normal(m.flatten(),v,samples)
gpplot(Xnew,m,m-2*np.sqrt(np.diag(v)[:,None]),m+2*np.sqrt(np.diag(v))[:,None])
for i in range(samples):
pb.plot(Xnew,Ysim[i,:],Tango.coloursHex['darkBlue'],linewidth=0.25)
pb.plot(self.X[which_data],self.likelihood.Y[which_data],'kx',mew=1.5)
pb.xlim(xmin,xmax)
ymin,ymax = min(np.append(self.likelihood.Y,m-2*np.sqrt(np.diag(v)[:,None]))), max(np.append(self.likelihood.Y,m+2*np.sqrt(np.diag(v)[:,None])))
ymin, ymax = ymin - 0.1*(ymax - ymin), ymax + 0.1*(ymax - ymin)
pb.ylim(ymin,ymax)
if hasattr(self,'Z'):
pb.plot(self.Z,self.Z*0+pb.ylim()[0],'r|',mew=1.5,markersize=12)
elif self.X.shape[1] == 2:
resolution = resolution or 50
Xnew, xmin, xmax, xx, yy = x_frame2D(self.X, plot_limits,resolution)
m,v = self._raw_predict(Xnew, slices=which_functions)
m = m.reshape(resolution,resolution).T
pb.contour(xx,yy,m,vmin=m.min(),vmax=m.max(),cmap=pb.cm.jet)
pb.scatter(Xorig[:,0],Xorig[:,1],40,Yorig,linewidth=0,cmap=pb.cm.jet,vmin=m.min(), vmax=m.max())
pb.xlim(xmin[0],xmax[0])
pb.ylim(xmin[1],xmax[1])
else:
raise NotImplementedError, "Cannot define a frame with more than two input dimensions"
def plot(self,samples=0,plot_limits=None,which_data='all',which_functions='all',resolution=None,full_cov=False):
# TODO include samples
if which_functions=='all':
which_functions = [True]*self.kern.Nparts
if which_data=='all':
which_data = slice(None)
if self.X.shape[1] == 1:
Xu = self.X * self._Xstd + self._Xmean #NOTE self.X are the normalized values now
Xnew, xmin, xmax = x_frame1D(Xu, plot_limits=plot_limits)
m, var, lower, upper = self.predict(Xnew, slices=which_functions)
gpplot(Xnew,m, lower, upper)
pb.plot(Xu[which_data],self.likelihood.data[which_data],'kx',mew=1.5)
ymin,ymax = min(np.append(self.likelihood.data,lower)), max(np.append(self.likelihood.data,upper))
ymin, ymax = ymin - 0.1*(ymax - ymin), ymax + 0.1*(ymax - ymin)
pb.xlim(xmin,xmax)
pb.ylim(ymin,ymax)
if hasattr(self,'Z'):
Zu = self.Z*self._Xstd + self._Xmean
pb.plot(Zu,Zu*0+pb.ylim()[0],'r|',mew=1.5,markersize=12)
elif self.X.shape[1]==2: #FIXME
resolution = resolution or 50
Xnew, xx, yy, xmin, xmax = x_frame2D(self.X, plot_limits,resolution)
x, y = np.linspace(xmin[0],xmax[0],resolution), np.linspace(xmin[1],xmax[1],resolution)
m, var, lower, upper = self.predict(Xnew, slices=which_functions)
m = m.reshape(resolution,resolution).T
pb.contour(x,y,m,vmin=m.min(),vmax=m.max(),cmap=pb.cm.jet)
Yf = self.likelihood.Y.flatten()
pb.scatter(self.X[:,0], self.X[:,1], 40, Yf, cmap=pb.cm.jet,vmin=m.min(),vmax=m.max(), linewidth=0.)
pb.xlim(xmin[0],xmax[0])
pb.ylim(xmin[1],xmax[1])
else:
raise NotImplementedError, "Cannot define a frame with more than two input dimensions"

View file

@ -8,9 +8,10 @@ import sys, pdb
from .. import kern from .. import kern
from ..core import model from ..core import model
from ..util.linalg import pdinv, PCA from ..util.linalg import pdinv, PCA
from GP_regression import GP_regression from GP import GP
from ..likelihoods import Gaussian
class GPLVM(GP_regression): class GPLVM(GP):
""" """
Gaussian Process Latent Variable Model Gaussian Process Latent Variable Model
@ -22,10 +23,13 @@ class GPLVM(GP_regression):
:type init: 'PCA'|'random' :type init: 'PCA'|'random'
""" """
def __init__(self, Y, Q, init='PCA', X = None, **kwargs): def __init__(self, Y, Q, init='PCA', X = None, kernel=None, **kwargs):
if X is None: if X is None:
X = self.initialise_latent(init, Q, Y) X = self.initialise_latent(init, Q, Y)
GP_regression.__init__(self, X, Y, **kwargs) if kernel is None:
kernel = kern.rbf(Q) + kern.bias(Q)
likelihood = Gaussian(Y)
GP.__init__(self, X, likelihood, kernel, **kwargs)
def initialise_latent(self, init, Q, Y): def initialise_latent(self, init, Q, Y):
if init == 'PCA': if init == 'PCA':
@ -34,23 +38,19 @@ class GPLVM(GP_regression):
return np.random.randn(Y.shape[0], Q) return np.random.randn(Y.shape[0], Q)
def _get_param_names(self): def _get_param_names(self):
return (sum([['X_%i_%i'%(n,q) for n in range(self.N)] for q in range(self.Q)],[]) return sum([['X_%i_%i'%(n,q) for n in range(self.N)] for q in range(self.Q)],[]) + GP._get_param_names(self)
+ self.kern._get_param_names_transformed())
def _get_params(self): def _get_params(self):
return np.hstack((self.X.flatten(), self.kern._get_params_transformed())) return np.hstack((self.X.flatten(), GP._get_params(self)))
def _set_params(self,x): def _set_params(self,x):
self.X = x[:self.X.size].reshape(self.N,self.Q).copy() self.X = x[:self.X.size].reshape(self.N,self.Q).copy()
GP_regression._set_params(self, x[self.X.size:]) GP._set_params(self, x[self.X.size:])
def _log_likelihood_gradients(self): def _log_likelihood_gradients(self):
dL_dK = self.dL_dK() dL_dX = 2.*self.kern.dK_dX(self.dL_dK,self.X)
dL_dtheta = self.kern.dK_dtheta(dL_dK,self.X) return np.hstack((dL_dX.flatten(),GP._log_likelihood_gradients(self)))
dL_dX = 2*self.kern.dK_dX(dL_dK,self.X)
return np.hstack((dL_dX.flatten(),dL_dtheta))
def plot(self): def plot(self):
assert self.Y.shape[1]==2 assert self.Y.shape[1]==2

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@ -1,160 +0,0 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
import pylab as pb
from scipy import stats, linalg
from .. import kern
from ..inference.Expectation_Propagation import Full
from ..inference.likelihoods import likelihood,probit#,poisson,gaussian
from ..core import model
from ..util.linalg import pdinv,jitchol
from ..util.plot import gpplot
class GP_EP(model):
def __init__(self,X,likelihood,kernel=None,epsilon_ep=1e-3,epsion_em=.1,powerep=[1.,1.]):
"""
Simple Gaussian Process with Non-Gaussian likelihood
Arguments
---------
:param X: input observations (NxD numpy.darray)
:param likelihood: a GPy likelihood (likelihood class)
:param kernel: a GPy kernel (kern class)
:param epsilon_ep: convergence criterion for the Expectation Propagation algorithm, defaults to 0.1 (float)
:param powerep: power-EP parameters [$\eta$,$\delta$], defaults to [1.,1.] (list)
:rtype: GPy model class.
"""
if kernel is None:
kernel = kern.rbf(X.shape[1]) + kern.bias(X.shape[1]) + kern.white(X.shape[1])
assert isinstance(kernel,kern.kern), 'kernel is not a kern instance'
self.likelihood = likelihood
self.Y = self.likelihood.Y
self.kernel = kernel
self.X = X
self.N, self.D = self.X.shape
self.eta,self.delta = powerep
self.epsilon_ep = epsilon_ep
self.jitter = 1e-12
self.K = self.kernel.K(self.X)
model.__init__(self)
def _set_params(self,p):
self.kernel._set_params_transformed(p)
def _get_params(self):
return self.kernel._get_params_transformed()
def _get_param_names(self):
return self.kernel._get_param_names_transformed()
def approximate_likelihood(self):
self.ep_approx = Full(self.K,self.likelihood,epsilon=self.epsilon_ep,powerep=[self.eta,self.delta])
self.ep_approx.fit_EP()
def posterior_param(self):
self.K = self.kernel.K(self.X)
self.Sroot_tilde_K = np.sqrt(self.ep_approx.tau_tilde)[:,None]*self.K
B = np.eye(self.N) + np.sqrt(self.ep_approx.tau_tilde)[None,:]*self.Sroot_tilde_K
#self.L = np.linalg.cholesky(B)
self.L = jitchol(B)
V,info = linalg.flapack.dtrtrs(self.L,self.Sroot_tilde_K,lower=1)
self.Sigma = self.K - np.dot(V.T,V)
self.mu = np.dot(self.Sigma,self.ep_approx.v_tilde)
def log_likelihood(self):
"""
Returns
-------
The EP approximation to the log-marginal likelihood
"""
self.posterior_param()
mu_ = self.ep_approx.v_/self.ep_approx.tau_
L1 =.5*sum(np.log(1+self.ep_approx.tau_tilde*1./self.ep_approx.tau_))-sum(np.log(np.diag(self.L)))
L2A =.5*np.sum((self.Sigma-np.diag(1./(self.ep_approx.tau_+self.ep_approx.tau_tilde))) * np.dot(self.ep_approx.v_tilde[:,None],self.ep_approx.v_tilde[None,:]))
L2B = .5*np.dot(mu_*(self.ep_approx.tau_/(self.ep_approx.tau_tilde+self.ep_approx.tau_)),self.ep_approx.tau_tilde*mu_ - 2*self.ep_approx.v_tilde)
L3 = sum(np.log(self.ep_approx.Z_hat))
return L1 + L2A + L2B + L3
def _log_likelihood_gradients(self):
dK_dp = self.kernel.dK_dtheta(self.X)
self.dK_dp = dK_dp
aux1,info_1 = linalg.flapack.dtrtrs(self.L,np.dot(self.Sroot_tilde_K,self.ep_approx.v_tilde),lower=1)
b = self.ep_approx.v_tilde - np.sqrt(self.ep_approx.tau_tilde)*linalg.flapack.dtrtrs(self.L.T,aux1)[0]
U,info_u = linalg.flapack.dtrtrs(self.L,np.diag(np.sqrt(self.ep_approx.tau_tilde)),lower=1)
dL_dK = 0.5*(np.outer(b,b)-np.dot(U.T,U))
self.dL_dK = dL_dK
return np.array([np.sum(dK_dpi*dL_dK) for dK_dpi in dK_dp.T])
def predict(self,X):
#TODO: check output dimensions
self.posterior_param()
K_x = self.kernel.K(self.X,X)
Kxx = self.kernel.K(X)
aux1,info = linalg.flapack.dtrtrs(self.L,np.dot(self.Sroot_tilde_K,self.ep_approx.v_tilde),lower=1)
aux2,info = linalg.flapack.dtrtrs(self.L.T, aux1,lower=0)
zeta = np.sqrt(self.ep_approx.tau_tilde)*aux2
f = np.dot(K_x.T,self.ep_approx.v_tilde-zeta)
v,info = linalg.flapack.dtrtrs(self.L,np.sqrt(self.ep_approx.tau_tilde)[:,None]*K_x,lower=1)
variance = Kxx - np.dot(v.T,v)
vdiag = np.diag(variance)
y=self.likelihood.predictive_mean(f,vdiag)
return f,vdiag,y
def plot(self):
"""
Plot the fitted model: training function values, inducing points used, mean estimate and confidence intervals.
"""
if self.X.shape[1]==1:
pb.figure()
xmin,xmax = self.X.min(),self.X.max()
xmin, xmax = xmin-0.2*(xmax-xmin), xmax+0.2*(xmax-xmin)
Xnew = np.linspace(xmin,xmax,100)[:,None]
mu_f, var_f, mu_phi = self.predict(Xnew)
pb.subplot(211)
self.likelihood.plot1Da(X_new=Xnew,Mean_new=mu_f,Var_new=var_f,X_u=self.X,Mean_u=self.mu,Var_u=np.diag(self.Sigma))
pb.subplot(212)
self.likelihood.plot1Db(self.X,Xnew,mu_phi)
elif self.X.shape[1]==2:
pb.figure()
x1min,x1max = self.X[:,0].min(0),self.X[:,0].max(0)
x2min,x2max = self.X[:,1].min(0),self.X[:,1].max(0)
x1min, x1max = x1min-0.2*(x1max-x1min), x1max+0.2*(x1max-x1min)
x2min, x2max = x2min-0.2*(x2max-x2min), x2max+0.2*(x1max-x1min)
axis1 = np.linspace(x1min,x1max,50)
axis2 = np.linspace(x2min,x2max,50)
XX1, XX2 = [e.flatten() for e in np.meshgrid(axis1,axis2)]
Xnew = np.c_[XX1.flatten(),XX2.flatten()]
f,v,p = self.predict(Xnew)
self.likelihood.plot2D(self.X,Xnew,p)
else:
raise NotImplementedError, "Cannot plot GPs with more than two input dimensions"
def em(self,max_f_eval=1e4,epsilon=.1,plot_all=False): #TODO check this makes sense
"""
Fits sparse_EP and optimizes the hyperparametes iteratively until convergence is achieved.
"""
self.epsilon_em = epsilon
log_likelihood_change = self.epsilon_em + 1.
self.parameters_path = [self.kernel._get_params()]
self.approximate_likelihood()
self.site_approximations_path = [[self.ep_approx.tau_tilde,self.ep_approx.v_tilde]]
self.log_likelihood_path = [self.log_likelihood()]
iteration = 0
while log_likelihood_change > self.epsilon_em:
print 'EM iteration', iteration
self.optimize(max_f_eval = max_f_eval)
log_likelihood_new = self.log_likelihood()
log_likelihood_change = log_likelihood_new - self.log_likelihood_path[-1]
if log_likelihood_change < 0:
print 'log_likelihood decrement'
self.kernel._set_params_transformed(self.parameters_path[-1])
self.kernM._set_params_transformed(self.parameters_path[-1])
else:
self.approximate_likelihood()
self.log_likelihood_path.append(self.log_likelihood())
self.parameters_path.append(self.kernel._get_params())
self.site_approximations_path.append([self.ep_approx.tau_tilde,self.ep_approx.v_tilde])
iteration += 1

View file

@ -1,18 +1,18 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt). # Copyright (c) 2012, James Hensman
# Licensed under the BSD 3-clause license (see LICENSE.txt) # Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np import numpy as np
import pylab as pb from GP import GP
from .. import likelihoods
from .. import kern from .. import kern
from ..core import model
from ..util.linalg import pdinv,mdot
from ..util.plot import gpplot, Tango
class GP_regression(model): class GP_regression(GP):
""" """
Gaussian Process model for regression Gaussian Process model for regression
This is a thin wrapper around the GP class, with a set of sensible defalts
:param X: input observations :param X: input observations
:param Y: observed values :param Y: observed values
:param kernel: a GPy kernel, defaults to rbf+white :param kernel: a GPy kernel, defaults to rbf+white
@ -29,199 +29,8 @@ class GP_regression(model):
def __init__(self,X,Y,kernel=None,normalize_X=False,normalize_Y=False, Xslices=None): def __init__(self,X,Y,kernel=None,normalize_X=False,normalize_Y=False, Xslices=None):
if kernel is None: if kernel is None:
kernel = kern.rbf(X.shape[1]) + kern.bias(X.shape[1]) + kern.white(X.shape[1]) kernel = kern.rbf(X.shape[1])
# parse arguments likelihood = likelihoods.Gaussian(Y,normalize=normalize_Y)
self.Xslices = Xslices
assert isinstance(kernel, kern.kern)
self.kern = kernel
self.X = X
self.Y = Y
assert len(self.X.shape)==2
assert len(self.Y.shape)==2
assert self.X.shape[0] == self.Y.shape[0]
self.N, self.D = self.Y.shape
self.N, self.Q = self.X.shape
#here's some simple normalisation GP.__init__(self, X, likelihood, kernel, normalize_X=normalize_X, Xslices=Xslices)
if normalize_X:
self._Xmean = X.mean(0)[None,:]
self._Xstd = X.std(0)[None,:]
self.X = (X.copy() - self._Xmean) / self._Xstd
if hasattr(self,'Z'):
self.Z = (self.Z - self._Xmean) / self._Xstd
else:
self._Xmean = np.zeros((1,self.X.shape[1]))
self._Xstd = np.ones((1,self.X.shape[1]))
if normalize_Y:
self._Ymean = Y.mean(0)[None,:]
self._Ystd = Y.std(0)[None,:]
self.Y = (Y.copy()- self._Ymean) / self._Ystd
else:
self._Ymean = np.zeros((1,self.Y.shape[1]))
self._Ystd = np.ones((1,self.Y.shape[1]))
if self.D > self.N:
# then it's more efficient to store YYT
self.YYT = np.dot(self.Y, self.Y.T)
else:
self.YYT = None
model.__init__(self)
def _set_params(self,p):
self.kern._set_params_transformed(p)
self.K = self.kern.K(self.X,slices1=self.Xslices)
self.Ki, self.L, self.Li, self.K_logdet = pdinv(self.K)
def _get_params(self):
return self.kern._get_params_transformed()
def _get_param_names(self):
return self.kern._get_param_names_transformed()
def _model_fit_term(self):
"""
Computes the model fit using YYT if it's available
"""
if self.YYT is None:
return -0.5*np.sum(np.square(np.dot(self.Li,self.Y)))
else:
return -0.5*np.sum(np.multiply(self.Ki, self.YYT))
def log_likelihood(self):
complexity_term = -0.5*self.N*self.D*np.log(2.*np.pi) - 0.5*self.D*self.K_logdet
return complexity_term + self._model_fit_term()
def dL_dK(self):
if self.YYT is None:
alpha = np.dot(self.Ki,self.Y)
dL_dK = 0.5*(np.dot(alpha,alpha.T)-self.D*self.Ki)
else:
dL_dK = 0.5*(mdot(self.Ki, self.YYT, self.Ki) - self.D*self.Ki)
return dL_dK
def _log_likelihood_gradients(self):
return self.kern.dK_dtheta(partial=self.dL_dK(),X=self.X)
def predict(self,Xnew, slices=None, full_cov=False):
"""
Predict the function(s) at the new point(s) Xnew.
Arguments
---------
:param Xnew: The points at which to make a prediction
:type Xnew: np.ndarray, Nnew x self.Q
:param slices: specifies which outputs kernel(s) the Xnew correspond to (see below)
:type slices: (None, list of slice objects, list of ints)
:param full_cov: whether to return the folll covariance matrix, or just the diagonal
:type full_cov: bool
:rtype: posterior mean, a Numpy array, Nnew x self.D
:rtype: posterior variance, a Numpy array, Nnew x Nnew x (self.D)
.. Note:: "slices" specifies how the the points X_new co-vary wich the training points.
- If None, the new points covary throigh every kernel part (default)
- If a list of slices, the i^th slice specifies which data are affected by the i^th kernel part
- If a list of booleans, specifying which kernel parts are active
If full_cov and self.D > 1, the return shape of var is Nnew x Nnew x self.D. If self.D == 1, the return shape is Nnew x Nnew.
This is to allow for different normalisations of the output dimensions.
"""
#normalise X values
Xnew = (Xnew.copy() - self._Xmean) / self._Xstd
mu, var = self._raw_predict(Xnew, slices, full_cov)
#un-normalise
mu = mu*self._Ystd + self._Ymean
if full_cov:
if self.D==1:
var *= np.square(self._Ystd)
else:
var = var[:,:,None] * np.square(self._Ystd)
else:
if self.D==1:
var *= np.square(np.squeeze(self._Ystd))
else:
var = var[:,None] * np.square(self._Ystd)
return mu,var
def _raw_predict(self,_Xnew,slices, full_cov=False):
"""Internal helper function for making predictions, does not account for normalisation"""
Kx = self.kern.K(self.X,_Xnew, slices1=self.Xslices,slices2=slices)
mu = np.dot(np.dot(Kx.T,self.Ki),self.Y)
KiKx = np.dot(self.Ki,Kx)
if full_cov:
Kxx = self.kern.K(_Xnew, slices1=slices,slices2=slices)
var = Kxx - np.dot(KiKx.T,Kx)
else:
Kxx = self.kern.Kdiag(_Xnew, slices=slices)
var = Kxx - np.sum(np.multiply(KiKx,Kx),0)
return mu, var
def plot(self,samples=0,plot_limits=None,which_data='all',which_functions='all',resolution=None):
"""
:param samples: the number of a posteriori samples to plot
:param which_data: which if the training data to plot (default all)
:type which_data: 'all' or a slice object to slice self.X, self.Y
:param plot_limits: The limits of the plot. If 1D [xmin,xmax], if 2D [[xmin,ymin],[xmax,ymax]]. Defaluts to data limits
:param which_functions: which of the kernel functions to plot (additively)
:type which_functions: list of bools
:param resolution: the number of intervals to sample the GP on. Defaults to 200 in 1D and 50 (a 50x50 grid) in 2D
Plot the posterior of the GP.
- In one dimension, the function is plotted with a shaded region identifying two standard deviations.
- In two dimsensions, a contour-plot shows the mean predicted function
- In higher dimensions, we've no implemented this yet !TODO!
Can plot only part of the data and part of the posterior functions using which_data and which_functions
"""
if which_functions=='all':
which_functions = [True]*self.kern.Nparts
if which_data=='all':
which_data = slice(None)
X = self.X[which_data,:]
Y = self.Y[which_data,:]
Xorig = X*self._Xstd + self._Xmean
Yorig = Y*self._Ystd + self._Ymean
if plot_limits is None:
xmin,xmax = Xorig.min(0),Xorig.max(0)
xmin, xmax = xmin-0.2*(xmax-xmin), xmax+0.2*(xmax-xmin)
elif len(plot_limits)==2:
xmin, xmax = plot_limits
else:
raise ValueError, "Bad limits for plotting"
if self.X.shape[1]==1:
Xnew = np.linspace(xmin,xmax,resolution or 200)[:,None]
m,v = self.predict(Xnew,slices=which_functions)
gpplot(Xnew,m,v)
if samples:
s = np.random.multivariate_normal(m.flatten(),v,samples)
pb.plot(Xnew.flatten(),s.T, alpha = 0.4, c='#3465a4', linewidth = 0.8)
pb.plot(Xorig,Yorig,'kx',mew=1.5)
pb.xlim(xmin,xmax)
elif self.X.shape[1]==2:
resolution = 50 or resolution
xx,yy = np.mgrid[xmin[0]:xmax[0]:1j*resolution,xmin[1]:xmax[1]:1j*resolution]
Xtest = np.vstack((xx.flatten(),yy.flatten())).T
zz,vv = self.predict(Xtest,slices=which_functions)
zz = zz.reshape(resolution,resolution)
pb.contour(xx,yy,zz,vmin=zz.min(),vmax=zz.max(),cmap=pb.cm.jet)
pb.scatter(Xorig[:,0],Xorig[:,1],40,Yorig,linewidth=0,cmap=pb.cm.jet,vmin=zz.min(),vmax=zz.max())
pb.xlim(xmin[0],xmax[0])
pb.ylim(xmin[1],xmax[1])
else:
raise NotImplementedError, "Cannot plot GPs with more than two input dimensions"

View file

@ -2,12 +2,12 @@
# Licensed under the BSD 3-clause license (see LICENSE.txt) # Licensed under the BSD 3-clause license (see LICENSE.txt)
from GP import GP
from GP_regression import GP_regression from GP_regression import GP_regression
from sparse_GP import sparse_GP
from sparse_GP_regression import sparse_GP_regression from sparse_GP_regression import sparse_GP_regression
from GPLVM import GPLVM from GPLVM import GPLVM
from warped_GP import warpedGP from warped_GP import warpedGP
from GP_EP import GP_EP
from generalized_FITC import generalized_FITC
from sparse_GPLVM import sparse_GPLVM from sparse_GPLVM import sparse_GPLVM
from uncollapsed_sparse_GP import uncollapsed_sparse_GP #from uncollapsed_sparse_GP import uncollapsed_sparse_GP
from BGPLVM import Bayesian_GPLVM from BGPLVM import Bayesian_GPLVM

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@ -1,241 +0,0 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
import pylab as pb
from scipy import stats, linalg
from .. import kern
from ..core import model
from ..util.linalg import pdinv,mdot
from ..util.plot import gpplot
from ..inference.Expectation_Propagation import FITC
from ..inference.likelihoods import likelihood,probit
class generalized_FITC(model):
def __init__(self,X,likelihood,kernel=None,inducing=10,epsilon_ep=1e-3,powerep=[1.,1.]):
"""
Naish-Guzman, A. and Holden, S. (2008) implemantation of EP with FITC.
:param X: input observations
:param likelihood: Output's likelihood (likelihood class)
:param kernel: a GPy kernel
:param inducing: Either an array specifying the inducing points location or a scalar defining their number.
:param epsilon_ep: EP convergence criterion, maximum squared difference allowed between mean updates to stop iterations (float)
:param powerep: Power-EP parameters (eta,delta) - 2x1 numpy array (floats)
"""
assert isinstance(kernel,kern.kern)
self.likelihood = likelihood
self.Y = self.likelihood.Y
self.kernel = kernel
self.X = X
self.N, self.D = self.X.shape
assert self.Y.shape[0] == self.N
if type(inducing) == int:
self.M = inducing
self.Z = (np.random.random_sample(self.D*self.M)*(self.X.max()-self.X.min())+self.X.min()).reshape(self.M,-1)
elif type(inducing) == np.ndarray:
self.Z = inducing
self.M = self.Z.shape[0]
self.eta,self.delta = powerep
self.epsilon_ep = epsilon_ep
self.jitter = 1e-12
model.__init__(self)
def _set_params(self,p):
self.kernel._set_params_transformed(p[0:-self.Z.size])
self.Z = p[-self.Z.size:].reshape(self.M,self.D)
def _get_params(self):
return np.hstack([self.kernel._get_params_transformed(),self.Z.flatten()])
def _get_param_names(self):
return self.kernel._get_param_names_transformed()+['iip_%i'%i for i in range(self.Z.size)]
def approximate_likelihood(self):
self.Kmm = self.kernel.K(self.Z)
self.Knm = self.kernel.K(self.X,self.Z)
self.Knn_diag = self.kernel.Kdiag(self.X)
self.ep_approx = FITC(self.Kmm,self.likelihood,self.Knm.T,self.Knn_diag,epsilon=self.epsilon_ep,powerep=[self.eta,self.delta])
self.ep_approx.fit_EP()
def posterior_param(self):
self.Knn_diag = self.kernel.Kdiag(self.X)
self.Kmm = self.kernel.K(self.Z)
self.Kmmi, self.Lmm, self.Lmmi, self.Kmm_logdet = pdinv(self.Kmm)
self.Knm = self.kernel.K(self.X,self.Z)
self.KmmiKmn = np.dot(self.Kmmi,self.Knm.T)
self.Qnn = np.dot(self.Knm,self.KmmiKmn)
self.Diag0 = self.Knn_diag - np.diag(self.Qnn)
self.R0 = np.linalg.cholesky(self.Kmmi).T
self.Taut = self.ep_approx.tau_tilde/(1.+ self.ep_approx.tau_tilde*self.Diag0)
self.KmnTaut = self.Knm.T*self.Taut[None,:]
self.KmnTautKnm = np.dot(self.KmnTaut, self.Knm)
self.Woodbury_inv, self.Wood_L, self.Wood_Li, self.Woodbury_logdet = pdinv(self.Kmm + self.KmnTautKnm)
self.Qnn_diag = self.Knn_diag - np.diag(self.Qnn) + 1./self.ep_approx.tau_tilde
self.Qi = -np.dot(self.KmnTaut.T, np.dot(self.Woodbury_inv,self.KmnTaut)) + np.diag(self.Taut)
self.hld = 0.5*np.sum(np.log(self.Diag0 + 1./self.ep_approx.tau_tilde)) - 0.5*self.Kmm_logdet + 0.5*self.Woodbury_logdet
self.Diag = self.Diag0/(1.+ self.Diag0 * self.ep_approx.tau_tilde)
self.P = (self.Diag / self.Diag0)[:,None] * self.Knm
self.RPT0 = np.dot(self.R0,self.Knm.T)
self.L = np.linalg.cholesky(np.eye(self.M) + np.dot(self.RPT0,(1./self.Diag0 - self.Diag/(self.Diag0**2))[:,None]*self.RPT0.T))
self.R,info = linalg.flapack.dtrtrs(self.L,self.R0,lower=1)
self.RPT = np.dot(self.R,self.P.T)
self.Sigma = np.diag(self.Diag) + np.dot(self.RPT.T,self.RPT)
self.w = self.Diag * self.ep_approx.v_tilde
self.gamma = np.dot(self.R.T, np.dot(self.RPT,self.ep_approx.v_tilde))
self.mu = self.w + np.dot(self.P,self.gamma)
self.mu_tilde = (self.ep_approx.v_tilde/self.ep_approx.tau_tilde)[:,None]
def log_likelihood(self):
self.posterior_param()
self.YYT = np.dot(self.mu_tilde,self.mu_tilde.T)
A = -self.hld
B = -.5*np.sum(self.Qi*self.YYT)
C = sum(np.log(self.ep_approx.Z_hat))
D = .5*np.sum(np.log(1./self.ep_approx.tau_tilde + 1./self.ep_approx.tau_))
E = .5*np.sum((self.ep_approx.v_/self.ep_approx.tau_ - self.mu_tilde.flatten())**2/(1./self.ep_approx.tau_ + 1./self.ep_approx.tau_tilde))
return A + B + C + D + E
def _log_likelihood_gradients(self):
dKmm_dtheta = self.kernel.dK_dtheta(self.Z)
dKnn_dtheta = self.kernel.dK_dtheta(self.X)
dKmn_dtheta = self.kernel.dK_dtheta(self.Z,self.X)
dKmm_dZ = -self.kernel.dK_dX(self.Z)
dKnm_dZ = -self.kernel.dK_dX(self.X,self.Z)
tmp = [np.dot(dKmn_dtheta_i,self.KmmiKmn) for dKmn_dtheta_i in dKmn_dtheta.T]
dQnn_dtheta = [tmp_i + tmp_i.T - np.dot(np.dot(self.KmmiKmn.T,dKmm_dtheta_i),self.KmmiKmn) for tmp_i,dKmm_dtheta_i in zip(tmp,dKmm_dtheta.T)]
dDiag0_dtheta = [np.diag(dKnn_dtheta_i) - np.diag(dQnn_dtheta_i) for dKnn_dtheta_i,dQnn_dtheta_i in zip(dKnn_dtheta.T,dQnn_dtheta)]
dQ_dtheta = [np.diag(dDiag0_dtheta_i) + dQnn_dtheta_i for dDiag0_dtheta_i,dQnn_dtheta_i in zip(dDiag0_dtheta,dQnn_dtheta)]
dW_dtheta = [dKmm_dtheta_i + 2*np.dot(self.KmnTaut,dKmn_dtheta_i) - np.dot(self.KmnTaut*dDiag0_dtheta_i,self.KmnTaut.T) for dKmm_dtheta_i,dDiag0_dtheta_i,dKmn_dtheta_i in zip(dKmm_dtheta.T,dDiag0_dtheta,dKmn_dtheta.T)]
QiY = np.dot(self.Qi, self.mu_tilde)
QiYYQi = np.outer(QiY,QiY)
WiKmnTaut = np.dot(self.Woodbury_inv,self.KmnTaut)
K_Y = np.dot(self.KmmiKmn,QiY)
# gradient - theta
Atheta = [-0.5*np.dot(self.Taut,dDiag0_dtheta_i) + 0.5*np.sum(self.Kmmi*dKmm_dtheta_i) - 0.5*np.sum(self.Woodbury_inv*dW_dtheta_i) for dDiag0_dtheta_i,dKmm_dtheta_i,dW_dtheta_i in zip(dDiag0_dtheta,dKmm_dtheta.T,dW_dtheta)]
Btheta = np.array([0.5*np.sum(QiYYQi*dQ_dtheta_i) for dQ_dtheta_i in dQ_dtheta])
dL_dtheta = Atheta + Btheta
# gradient - Z
# Az
dQnn_dZ_diag_a2 = (np.array([d[:,:,None]*self.KmmiKmn[:,:,None] for d in dKnm_dZ.transpose(2,0,1)]).reshape(self.D,self.M,self.N)).transpose(1,2,0)
dQnn_dZ_diag_b2 = (np.array([(self.KmmiKmn*np.sum(d[:,:,None]*self.KmmiKmn,-2))[:,:,None] for d in dKmm_dZ.transpose(2,0,1)]).reshape(self.D,self.M,self.N)).transpose(1,2,0)
dQnn_dZ_diag = dQnn_dZ_diag_a2 - dQnn_dZ_diag_b2
d_hld_Diag1_dZ = -np.sum(np.dot(self.KmmiKmn*self.Taut,self.KmmiKmn.T)[:,:,None]*dKmm_dZ,-2) + np.sum((self.KmmiKmn*self.Taut)[:,:,None]*dKnm_dZ,-2)
d_hld_Kmm_dZ = np.sum(self.Kmmi[:,:,None]*dKmm_dZ,-2)
d_hld_W_dZ1 = np.sum(WiKmnTaut[:,:,None]*dKnm_dZ,-2)
d_hld_W_dZ3 = np.sum(self.Woodbury_inv[:,:,None]*dKmm_dZ,-2)
d_hld_W_dZ2 = np.array([np.sum(np.sum(WiKmnTaut.T*d[:,:,None]*self.KmnTaut.T,-2),-1) for d in dQnn_dZ_diag.transpose(2,0,1)]).T
Az = d_hld_Diag1_dZ + d_hld_Kmm_dZ - d_hld_W_dZ1 - d_hld_W_dZ2 - d_hld_W_dZ3
# Bz
Bz2 = np.sum(np.dot(K_Y,QiY.T)[:,:,None]*dKnm_dZ,-2)
Bz3 = - np.sum(np.dot(K_Y,K_Y.T)[:,:,None]*dKmm_dZ,-2)
Bz1 = -np.array([np.sum((QiY**2)*d[:,:,None],-2) for d in dQnn_dZ_diag.transpose(2,0,1)]).reshape(self.D,self.M).T
Bz = Bz1 + Bz2 + Bz3
dL_dZ = (Az + Bz).flatten()
return np.hstack([dL_dtheta, dL_dZ])
def predict(self,X):
"""
Make a prediction for the vsGP model
Arguments
---------
X : Input prediction data - Nx1 numpy array (floats)
"""
#TODO: check output dimensions
K_x = self.kernel.K(self.Z,X)
Kxx = self.kernel.K(X)
#K_x = self.kernM.cross.K(X)
# q(u|f) = N(u| R0i*mu_u*f, R0i*C*R0i.T)
# Ci = I + (RPT0)Di(RPT0).T
# C = I - [RPT0] * (D+[RPT0].T*[RPT0])^-1*[RPT0].T
# = I - [RPT0] * (D + self.Qnn)^-1 * [RPT0].T
# = I - [RPT0] * (U*U.T)^-1 * [RPT0].T
# = I - V.T * V
U = np.linalg.cholesky(np.diag(self.Diag0) + self.Qnn)
V,info = linalg.flapack.dtrtrs(U,self.RPT0.T,lower=1)
C = np.eye(self.M) - np.dot(V.T,V)
mu_u = np.dot(C,self.RPT0)*(1./self.Diag0[None,:])
#self.C = C
#self.RPT0 = np.dot(self.R0,self.Knm.T) P0.T
#self.mu_u = mu_u
#self.U = U
# q(u|y) = N(u| R0i*mu_H,R0i*Sigma_H*R0i.T)
mu_H = np.dot(mu_u,self.mu)
self.mu_H = mu_H
Sigma_H = C + np.dot(mu_u,np.dot(self.Sigma,mu_u.T))
# q(f_star|y) = N(f_star|mu_star,sigma2_star)
KR0T = np.dot(K_x.T,self.R0.T)
mu_star = np.dot(KR0T,mu_H)
sigma2_star = Kxx + np.dot(KR0T,np.dot(Sigma_H - np.eye(self.M),KR0T.T))
vdiag = np.diag(sigma2_star)
# q(y_star|y) = non-gaussian posterior probability of class membership
p = self.likelihood.predictive_mean(mu_star,vdiag)
return mu_star,vdiag,p
def plot(self):
"""
Plot the fitted model: training function values, inducing points used, mean estimate and confidence intervals.
"""
if self.X.shape[1]==1:
pb.figure()
xmin,xmax = np.r_[self.X,self.Z].min(),np.r_[self.X,self.Z].max()
xmin, xmax = xmin-0.2*(xmax-xmin), xmax+0.2*(xmax-xmin)
Xnew = np.linspace(xmin,xmax,100)[:,None]
mu_f, var_f, mu_phi = self.predict(Xnew)
self.mu_inducing,self.var_diag_inducing,self.phi_inducing = self.predict(self.Z)
pb.subplot(211)
self.likelihood.plot1Da(X_new=Xnew,Mean_new=mu_f,Var_new=var_f,X_u=self.Z,Mean_u=self.mu_inducing,Var_u=self.var_diag_inducing)
pb.subplot(212)
self.likelihood.plot1Db(self.X,Xnew,mu_phi,self.Z)
elif self.X.shape[1]==2:
pb.figure()
x1min,x1max = self.X[:,0].min(0),self.X[:,0].max(0)
x2min,x2max = self.X[:,1].min(0),self.X[:,1].max(0)
x1min, x1max = x1min-0.2*(x1max-x1min), x1max+0.2*(x1max-x1min)
x2min, x2max = x2min-0.2*(x2max-x2min), x2max+0.2*(x1max-x1min)
axis1 = np.linspace(x1min,x1max,50)
axis2 = np.linspace(x2min,x2max,50)
XX1, XX2 = [e.flatten() for e in np.meshgrid(axis1,axis2)]
Xnew = np.c_[XX1.flatten(),XX2.flatten()]
f,v,p = self.predict(Xnew)
self.likelihood.plot2D(self.X,Xnew,p,self.Z)
else:
raise NotImplementedError, "Cannot plot GPs with more than two input dimensions"
def em(self,max_f_eval=1e4,epsilon=.1,plot_all=False): #TODO check this makes sense
"""
Fits sparse_EP and optimizes the hyperparametes iteratively until convergence is achieved.
"""
self.epsilon_em = epsilon
log_likelihood_change = self.epsilon_em + 1.
self.parameters_path = [self.kernel._get_params()]
self.approximate_likelihood()
self.site_approximations_path = [[self.ep_approx.tau_tilde,self.ep_approx.v_tilde]]
self.inducing_inputs_path = [self.Z]
self.log_likelihood_path = [self.log_likelihood()]
iteration = 0
while log_likelihood_change > self.epsilon_em:
print 'EM iteration', iteration
self.optimize(max_f_eval = max_f_eval)
log_likelihood_new = self.log_likelihood()
log_likelihood_change = log_likelihood_new - self.log_likelihood_path[-1]
if log_likelihood_change < 0:
print 'log_likelihood decrement'
self.kernel._set_params_transformed(self.parameters_path[-1])
self.kernM = self.kernel.copy()
slef.kernM.expand_X(self.iducing_inputs_path[-1])
self.__init__(self.kernel,self.likelihood,kernM=self.kernM,powerep=[self.eta,self.delta],epsilon_ep = self.epsilon_ep, epsilon_em = self.epsilon_em)
else:
self.approximate_likelihood()
self.log_likelihood_path.append(self.log_likelihood())
self.parameters_path.append(self.kernel._get_params())
self.site_approximations_path.append([self.ep_approx.tau_tilde,self.ep_approx.v_tilde])
self.inducing_inputs_path.append(self.Z)
iteration += 1

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GPy/models/sparse_GP.py Normal file
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# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
import pylab as pb
from ..util.linalg import mdot, jitchol, chol_inv, pdinv
from ..util.plot import gpplot
from .. import kern
from GP import GP
#Still TODO:
# make use of slices properly (kernel can now do this)
# enable heteroscedatic noise (kernel will need to compute psi2 as a (NxMxM) array)
class sparse_GP(GP):
"""
Variational sparse GP model
:param X: inputs
:type X: np.ndarray (N x Q)
:param likelihood: a likelihood instance, containing the observed data
:type likelihood: GPy.likelihood.(Gaussian | EP)
:param kernel : the kernel/covariance function. See link kernels
:type kernel: a GPy kernel
:param X_uncertainty: The uncertainty in the measurements of X (Gaussian variance)
:type X_uncertainty: np.ndarray (N x Q) | None
:param Z: inducing inputs (optional, see note)
:type Z: np.ndarray (M x Q) | None
:param Zslices: slices for the inducing inputs (see slicing TODO: link)
:param M : Number of inducing points (optional, default 10. Ignored if Z is not None)
:type M: int
:param normalize_(X|Y) : whether to normalize the data before computing (predictions will be in original scales)
:type normalize_(X|Y): bool
"""
def __init__(self, X, likelihood, kernel, Z, X_uncertainty=None, Xslices=None,Zslices=None, normalize_X=False):
self.scale_factor = 1.0# a scaling factor to help keep the algorithm stable
self.Z = Z
self.Zslices = Zslices
self.Xslices = Xslices
self.M = Z.shape[0]
self.likelihood = likelihood
if X_uncertainty is None:
self.has_uncertain_inputs=False
else:
assert X_uncertainty.shape==X.shape
self.has_uncertain_inputs=True
self.X_uncertainty = X_uncertainty
GP.__init__(self, X, likelihood, kernel=kernel, normalize_X=normalize_X, Xslices=Xslices)
#normalise X uncertainty also
if self.has_uncertain_inputs:
self.X_uncertainty /= np.square(self._Xstd)
def _computations(self):
# TODO find routine to multiply triangular matrices
#TODO: slices for psi statistics (easy enough)
sf = self.scale_factor
sf2 = sf**2
# kernel computations, using BGPLVM notation
self.Kmm = self.kern.K(self.Z)
if self.has_uncertain_inputs:
self.psi0 = self.kern.psi0(self.Z,self.X, self.X_uncertainty)
self.psi1 = self.kern.psi1(self.Z,self.X, self.X_uncertainty).T
self.psi2 = self.kern.psi2(self.Z,self.X, self.X_uncertainty)
if self.likelihood.is_heteroscedastic:
self.psi2_beta_scaled = (self.psi2*(self.likelihood.precision.reshape(self.N,1,1)/sf2)).sum(0)
#TODO: what is the likelihood is heterscedatic and there are multiple independent outputs?
else:
self.psi2_beta_scaled = (self.psi2*(self.likelihood.precision/sf2)).sum(0)
else:
self.psi0 = self.kern.Kdiag(self.X,slices=self.Xslices)
self.psi1 = self.kern.K(self.Z,self.X)
if self.likelihood.is_heteroscedastic:
tmp = self.psi1*(np.sqrt(self.likelihood.precision.reshape(self.N,1))/sf)
else:
tmp = self.psi1*(np.sqrt(self.likelihood.precision)/sf)
self.psi2_beta_scaled = np.dot(tmp,tmp.T)
self.psi2 = self.psi1.T[:,:,None]*self.psi1.T[:,None,:] # TODO: remove me for efficiency and stability
self.Kmmi, self.Lm, self.Lmi, self.Kmm_logdet = pdinv(self.Kmm)
self.V = (self.likelihood.precision/self.scale_factor)*self.likelihood.Y
self.A = mdot(self.Lmi, self.psi2_beta_scaled, self.Lmi.T)
self.B = np.eye(self.M)/sf2 + self.A
self.Bi, self.LB, self.LBi, self.B_logdet = pdinv(self.B)
self.psi1V = np.dot(self.psi1, self.V)
self.psi1VVpsi1 = np.dot(self.psi1V, self.psi1V.T)
self.C = mdot(self.Lmi.T, self.Bi, self.Lmi)
self.E = mdot(self.C, self.psi1VVpsi1/sf2, self.C.T)
# Compute dL_dpsi # FIXME: this is untested for the het. case
self.dL_dpsi0 = - 0.5 * self.D * self.likelihood.precision * np.ones(self.N)
self.dL_dpsi1 = mdot(self.V, self.psi1V.T,self.C).T
if self.likelihood.is_heteroscedastic:
self.dL_dpsi2 = 0.5 * self.likelihood.precision[:,None,None] * self.D * self.Kmmi[None,:,:] # dB
self.dL_dpsi2 += - 0.5 * self.likelihood.precision[:,None,None]/sf2 * self.D * self.C[None,:,:] # dC
self.dL_dpsi2 += - 0.5 * self.likelihood.precision[:,None,None]* self.E[None,:,:] # dD
else:
self.dL_dpsi2 = 0.5 * self.likelihood.precision * self.D * self.Kmmi[None,:,:] # dB
self.dL_dpsi2 += - 0.5 * self.likelihood.precision/sf2 * self.D * self.C[None,:,:] # dC
self.dL_dpsi2 += - 0.5 * self.likelihood.precision * self.E[None,:,:] # dD
# Compute dL_dKmm
self.dL_dKmm = -0.5 * self.D * mdot(self.Lmi.T, self.A, self.Lmi)*sf2 # dB
self.dL_dKmm += -0.5 * self.D * (- self.C/sf2 - 2.*mdot(self.C, self.psi2_beta_scaled, self.Kmmi) + self.Kmmi) # dC
self.dL_dKmm += np.dot(np.dot(self.E*sf2, self.psi2_beta_scaled) - np.dot(self.C, self.psi1VVpsi1), self.Kmmi) + 0.5*self.E # dD
#the partial derivative vector for the likelihood
if self.likelihood.Nparams ==0:
#save computation here.
self.partial_for_likelihood = None
elif self.likelihood.is_heteroscedastic:
raise NotImplementedError, "heteroscedatic derivates not implemented"
#self.partial_for_likelihood = - 0.5 * self.D*self.likelihood.precision + 0.5 * (self.likelihood.Y**2).sum(1)*self.likelihood.precision**2 #dA
#self.partial_for_likelihood += 0.5 * self.D * (self.psi0*self.likelihood.precision**2 - (self.psi2*self.Kmmi[None,:,:]*self.likelihood.precision[:,None,None]**2).sum(1).sum(1)/sf2) #dB
#self.partial_for_likelihood += 0.5 * self.D * np.sum(self.Bi*self.A)*self.likelihood.precision #dC
#self.partial_for_likelihood += -np.diag(np.dot((self.C - 0.5 * mdot(self.C,self.psi2_beta_scaled,self.C) ) , self.psi1VVpsi1 ))*self.likelihood.precision #dD
else:
#likelihood is not heterscedatic
beta = self.likelihood.precision
dbeta = 0.5 * self.N*self.D/beta - 0.5 * np.sum(np.square(self.likelihood.Y))
dbeta += - 0.5 * self.D * (self.psi0.sum() - np.trace(self.A)/beta*sf2)
dbeta += - 0.5 * self.D * np.sum(self.Bi*self.A)/beta
dbeta += np.sum((self.C - 0.5 * mdot(self.C,self.psi2_beta_scaled,self.C) ) * self.psi1VVpsi1 )/beta
self.partial_for_likelihood = -dbeta*self.likelihood.precision**2
def _set_params(self, p):
self.Z = p[:self.M*self.Q].reshape(self.M, self.Q)
self.kern._set_params(p[self.Z.size:self.Z.size+self.kern.Nparam])
self.likelihood._set_params(p[self.Z.size+self.kern.Nparam:])
self._computations()
def _get_params(self):
return np.hstack([self.Z.flatten(),GP._get_params(self)])
def _get_param_names(self):
return sum([['iip_%i_%i'%(i,j) for i in range(self.Z.shape[0])] for j in range(self.Z.shape[1])],[]) + GP._get_param_names(self)
def log_likelihood(self):
""" Compute the (lower bound on the) log marginal likelihood """
sf2 = self.scale_factor**2
if self.likelihood.is_heteroscedastic:
A = -0.5*self.N*self.D*np.log(2.*np.pi) +0.5*np.sum(np.log(self.likelihood.precision)) -0.5*np.sum(self.V*self.likelihood.Y)
else:
A = -0.5*self.N*self.D*(np.log(2.*np.pi) - np.log(self.likelihood.precision)) -0.5*self.likelihood.precision*self.likelihood.trYYT
B = -0.5*self.D*(np.sum(self.likelihood.precision*self.psi0) - np.trace(self.A)*sf2)
C = -0.5*self.D * (self.B_logdet + self.M*np.log(sf2))
D = +0.5*np.sum(self.psi1VVpsi1 * self.C)
return A+B+C+D
def _log_likelihood_gradients(self):
return np.hstack((self.dL_dZ().flatten(), self.dL_dtheta(), self.likelihood._gradients(partial=self.partial_for_likelihood)))
def dL_dtheta(self):
"""
Compute and return the derivative of the log marginal likelihood wrt the parameters of the kernel
"""
dL_dtheta = self.kern.dK_dtheta(self.dL_dKmm,self.Z)
if self.has_uncertain_inputs:
dL_dtheta += self.kern.dpsi0_dtheta(self.dL_dpsi0, self.Z,self.X,self.X_uncertainty)
dL_dtheta += self.kern.dpsi1_dtheta(self.dL_dpsi1.T,self.Z,self.X, self.X_uncertainty)
dL_dtheta += self.kern.dpsi2_dtheta(self.dL_dpsi2,self.dL_dpsi1.T, self.Z,self.X, self.X_uncertainty)
else:
#re-cast computations in psi2 back to psi1:
dL_dpsi1 = self.dL_dpsi1 + 2.*np.dot(self.dL_dpsi2.sum(0),self.psi1)
dL_dtheta += self.kern.dK_dtheta(dL_dpsi1,self.Z,self.X)
dL_dtheta += self.kern.dKdiag_dtheta(self.dL_dpsi0, self.X)
return dL_dtheta
def dL_dZ(self):
"""
The derivative of the bound wrt the inducing inputs Z
"""
dL_dZ = 2.*self.kern.dK_dX(self.dL_dKmm,self.Z)#factor of two becase of vertical and horizontal 'stripes' in dKmm_dZ
if self.has_uncertain_inputs:
dL_dZ += self.kern.dpsi1_dZ(self.dL_dpsi1,self.Z,self.X, self.X_uncertainty)
dL_dZ += 2.*self.kern.dpsi2_dZ(self.dL_dpsi2,self.Z,self.X, self.X_uncertainty) # 'stripes'
else:
#re-cast computations in psi2 back to psi1:
dL_dpsi1 = self.dL_dpsi1 + 2.*np.dot(self.dL_dpsi2.sum(0),self.psi1)
dL_dZ += self.kern.dK_dX(dL_dpsi1,self.Z,self.X)
return dL_dZ
def _raw_predict(self, Xnew, slices, full_cov=False):
"""Internal helper function for making predictions, does not account for normalisation"""
Kx = self.kern.K(self.Z, Xnew)
mu = mdot(Kx.T, self.C/self.scale_factor, self.psi1V)
if full_cov:
Kxx = self.kern.K(Xnew)
var = Kxx - mdot(Kx.T, (self.Kmmi - self.C/self.scale_factor**2), Kx) #NOTE this won't work for plotting
else:
Kxx = self.kern.Kdiag(Xnew)
var = Kxx - np.sum(Kx*np.dot(self.Kmmi - self.C/self.scale_factor**2, Kx),0)
return mu,var[:,None]
def plot(self, *args, **kwargs):
"""
Plot the fitted model: just call the GP plot function and then add inducing inputs
"""
GP.plot(self,*args,**kwargs)
if self.Q==1:
if self.has_uncertain_inputs:
pb.errorbar(self.X[:,0], pb.ylim()[0]+np.zeros(self.N), xerr=2*np.sqrt(self.X_uncertainty.flatten()))
if self.Q==2:
pb.plot(self.Z[:,0],self.Z[:,1],'wo')

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@ -1,205 +1,44 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt). # Copyright (c) 2012, James Hensman
# Licensed under the BSD 3-clause license (see LICENSE.txt) # Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np import numpy as np
import pylab as pb from sparse_GP import sparse_GP
from ..util.linalg import mdot, jitchol, chol_inv, pdinv from .. import likelihoods
from ..util.plot import gpplot
from .. import kern from .. import kern
from ..inference.likelihoods import likelihood
from GP_regression import GP_regression
#Still TODO: class sparse_GP_regression(sparse_GP):
# make use of slices properly (kernel can now do this)
# enable heteroscedatic noise (kernel will need to compute psi2 as a (NxMxM) array)
class sparse_GP_regression(GP_regression):
""" """
Variational sparse GP model (Regression) Gaussian Process model for regression
This is a thin wrapper around the GP class, with a set of sensible defalts
:param X: input observations
:param Y: observed values
:param kernel: a GPy kernel, defaults to rbf+white
:param normalize_X: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_X: False|True
:param normalize_Y: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_Y: False|True
:param Xslices: how the X,Y data co-vary in the kernel (i.e. which "outputs" they correspond to). See (link:slicing)
:rtype: model object
.. Note:: Multiple independent outputs are allowed using columns of Y
:param X: inputs
:type X: np.ndarray (N x Q)
:param Y: observed data
:type Y: np.ndarray of observations (N x D)
:param kernel : the kernel/covariance function. See link kernels
:type kernel: a GPy kernel
:param Z: inducing inputs (optional, see note)
:type Z: np.ndarray (M x Q) | None
:param X_uncertainty: The uncertainty in the measurements of X (Gaussian variance)
:type X_uncertainty: np.ndarray (N x Q) | None
:param Zslices: slices for the inducing inputs (see slicing TODO: link)
:param M : Number of inducing points (optional, default 10. Ignored if Z is not None)
:type M: int
:param beta: noise precision. TODO> ignore beta if doing EP
:type beta: float
:param normalize_(X|Y) : whether to normalize the data before computing (predictions will be in original scales)
:type normalize_(X|Y): bool
""" """
def __init__(self,X,Y,kernel=None, X_uncertainty=None, beta=100., Z=None,Zslices=None,M=10,normalize_X=False,normalize_Y=False): def __init__(self,X,Y,kernel=None,normalize_X=False,normalize_Y=False, Xslices=None,Z=None, M=10):
self.scale_factor = 1000.0 #kern defaults to rbf
self.beta = beta if kernel is None:
kernel = kern.rbf(X.shape[1]) + kern.white(X.shape[1],1e-3)
#Z defaults to a subset of the data
if Z is None: if Z is None:
self.Z = np.random.permutation(X.copy())[:M] Z = np.random.permutation(X.copy())[:M]
self.M = M
else: else:
assert Z.shape[1]==X.shape[1] assert Z.shape[1]==X.shape[1]
self.Z = Z
self.M = Z.shape[0]
if X_uncertainty is None:
self.has_uncertain_inputs=False
else:
assert X_uncertainty.shape==X.shape
self.has_uncertain_inputs=True
self.X_uncertainty = X_uncertainty
GP_regression.__init__(self, X, Y, kernel=kernel, normalize_X=normalize_X, normalize_Y=normalize_Y) #likelihood defaults to Gaussian
self.trYYT = np.sum(np.square(self.Y)) likelihood = likelihoods.Gaussian(Y,normalize=normalize_Y)
#normalise X uncertainty also sparse_GP.__init__(self, X, likelihood, kernel, Z, normalize_X=normalize_X, Xslices=Xslices)
if self.has_uncertain_inputs:
self.X_uncertainty /= np.square(self._Xstd)
def _computations(self):
# TODO find routine to multiply triangular matrices
#TODO: slices for psi statistics (easy enough)
# kernel computations, using BGPLVM notation
self.Kmm = self.kern.K(self.Z)
if self.has_uncertain_inputs:
self.psi0 = self.kern.psi0(self.Z,self.X, self.X_uncertainty).sum()
self.psi1 = self.kern.psi1(self.Z,self.X, self.X_uncertainty).T
self.psi2 = self.kern.psi2(self.Z,self.X, self.X_uncertainty)
self.psi2_beta_scaled = (self.psi2*(self.beta/self.scale_factor**2)).sum(0)
else:
self.psi0 = self.kern.Kdiag(self.X,slices=self.Xslices).sum()
self.psi1 = self.kern.K(self.Z,self.X)
#self.psi2 = np.dot(self.psi1,self.psi1.T)
#self.psi2 = self.psi1.T[:,:,None]*self.psi1.T[:,None,:]
tmp = self.psi1/(self.scale_factor/np.sqrt(self.beta))
self.psi2_beta_scaled = np.dot(tmp,tmp.T)
sf = self.scale_factor
sf2 = sf**2
self.Kmmi, self.Lm, self.Lmi, self.Kmm_logdet = pdinv(self.Kmm)#+np.eye(self.M)*1e-3)
self.V = (self.beta/self.scale_factor)*self.Y
self.A = mdot(self.Lmi, self.psi2_beta_scaled, self.Lmi.T)
self.B = np.eye(self.M)/sf2 + self.A
self.Bi, self.LB, self.LBi, self.B_logdet = pdinv(self.B)
self.psi1V = np.dot(self.psi1, self.V)
self.psi1VVpsi1 = np.dot(self.psi1V, self.psi1V.T)
self.C = mdot(self.Lmi.T, self.Bi, self.Lmi)
self.E = mdot(self.C, self.psi1VVpsi1/sf2, self.C.T)
# Compute dL_dpsi
self.dL_dpsi0 = - 0.5 * self.D * self.beta * np.ones(self.N)
self.dL_dpsi1 = mdot(self.V, self.psi1V.T,self.C).T
self.dL_dpsi2 = 0.5 * self.beta * self.D * self.Kmmi[None,:,:] # dB
self.dL_dpsi2 += - 0.5 * self.beta/sf2 * self.D * self.C[None,:,:] # dC
self.dL_dpsi2 += - 0.5 * self.beta * self.E[None,:,:] # dD
# Compute dL_dKmm
self.dL_dKmm = -0.5 * self.D * mdot(self.Lmi.T, self.A, self.Lmi)*sf2 # dB
self.dL_dKmm += -0.5 * self.D * (- self.C/sf2 - 2.*mdot(self.C, self.psi2_beta_scaled, self.Kmmi) + self.Kmmi) # dC
self.dL_dKmm += np.dot(np.dot(self.E*sf2, self.psi2_beta_scaled) - np.dot(self.C, self.psi1VVpsi1), self.Kmmi) + 0.5*self.E # dD
def _set_params(self, p):
self.Z = p[:self.M*self.Q].reshape(self.M, self.Q)
self.beta = p[self.M*self.Q]
self.kern._set_params(p[self.Z.size + 1:])
self._computations()
def _get_params(self):
return np.hstack([self.Z.flatten(),self.beta,self.kern._get_params_transformed()])
def _get_param_names(self):
return sum([['iip_%i_%i'%(i,j) for i in range(self.Z.shape[0])] for j in range(self.Z.shape[1])],[]) + ['noise_precision']+self.kern._get_param_names_transformed()
def log_likelihood(self):
""" Compute the (lower bound on the) log marginal likelihood """
sf2 = self.scale_factor**2
A = -0.5*self.N*self.D*(np.log(2.*np.pi) - np.log(self.beta)) -0.5*self.beta*self.trYYT
B = -0.5*self.D*(self.beta*self.psi0-np.trace(self.A)*sf2)
C = -0.5*self.D * (self.B_logdet + self.M*np.log(sf2))
D = +0.5*np.sum(self.psi1VVpsi1 * self.C)
return A+B+C+D
def _log_likelihood_gradients(self):
return np.hstack([self.dL_dZ().flatten(), self.dL_dbeta(), self.dL_dtheta()])
def dL_dbeta(self):
"""
Compute the gradient of the log likelihood wrt beta.
"""
#TODO: suport heteroscedatic noise
sf2 = self.scale_factor**2
dA_dbeta = 0.5 * self.N*self.D/self.beta - 0.5 * self.trYYT
dB_dbeta = - 0.5 * self.D * (self.psi0 - np.trace(self.A)/self.beta*sf2)
dC_dbeta = - 0.5 * self.D * np.sum(self.Bi*self.A)/self.beta
dD_dbeta = np.sum((self.C - 0.5 * mdot(self.C,self.psi2_beta_scaled,self.C) ) * self.psi1VVpsi1 )/self.beta
return np.squeeze(dA_dbeta + dB_dbeta + dC_dbeta + dD_dbeta)
def dL_dtheta(self):
"""
Compute and return the derivative of the log marginal likelihood wrt the parameters of the kernel
"""
dL_dtheta = self.kern.dK_dtheta(self.dL_dKmm,self.Z)
if self.has_uncertain_inputs:
dL_dtheta += self.kern.dpsi0_dtheta(self.dL_dpsi0, self.Z,self.X,self.X_uncertainty)
dL_dtheta += self.kern.dpsi1_dtheta(self.dL_dpsi1.T,self.Z,self.X, self.X_uncertainty)
dL_dtheta += self.kern.dpsi2_dtheta(self.dL_dpsi2,self.dL_dpsi1.T, self.Z,self.X, self.X_uncertainty) # for multiple_beta, dL_dpsi2 will be a different shape
else:
#re-cast computations in psi2 back to psi1:
dL_dpsi1 = self.dL_dpsi1 + 2.*np.dot(self.dL_dpsi2.sum(0),self.psi1)
dL_dtheta += self.kern.dK_dtheta(dL_dpsi1,self.Z,self.X)
dL_dtheta += self.kern.dKdiag_dtheta(self.dL_dpsi0, self.X)
return dL_dtheta
def dL_dZ(self):
"""
The derivative of the bound wrt the inducing inputs Z
"""
dL_dZ = 2.*self.kern.dK_dX(self.dL_dKmm,self.Z)#factor of two becase of vertical and horizontal 'stripes' in dKmm_dZ
if self.has_uncertain_inputs:
dL_dZ += self.kern.dpsi1_dZ(self.dL_dpsi1,self.Z,self.X, self.X_uncertainty)
dL_dZ += 2.*self.kern.dpsi2_dZ(self.dL_dpsi2,self.Z,self.X, self.X_uncertainty) # 'stripes'
else:
#re-cast computations in psi2 back to psi1:
dL_dpsi1 = self.dL_dpsi1 + 2.*np.dot(self.dL_dpsi2.sum(0),self.psi1)
dL_dZ += self.kern.dK_dX(dL_dpsi1,self.Z,self.X)
return dL_dZ
def _raw_predict(self, Xnew, slices, full_cov=False):
"""Internal helper function for making predictions, does not account for normalisation"""
Kx = self.kern.K(self.Z, Xnew)
mu = mdot(Kx.T, self.C/self.scale_factor, self.psi1V)
if full_cov:
Kxx = self.kern.K(Xnew)
var = Kxx - mdot(Kx.T, (self.Kmmi - self.C/self.scale_factor**2), Kx) + np.eye(Xnew.shape[0])/self.beta # TODO: This beta doesn't belong here in the EP case.
else:
Kxx = self.kern.Kdiag(Xnew)
var = Kxx - np.sum(Kx*np.dot(self.Kmmi - self.C/self.scale_factor**2, Kx),0) + 1./self.beta # TODO: This beta doesn't belong here in the EP case.
return mu,var
def plot(self, *args, **kwargs):
"""
Plot the fitted model: just call the GP_regression plot function and then add inducing inputs
"""
GP_regression.plot(self,*args,**kwargs)
if self.Q==1:
pb.plot(self.Z,self.Z*0+pb.ylim()[0],'k|',mew=1.5,markersize=12)
if self.has_uncertain_inputs:
pb.errorbar(self.X[:,0], pb.ylim()[0]+np.zeros(self.N), xerr=2*np.sqrt(self.X_uncertainty.flatten()))
if self.Q==2:
pb.plot(self.Z[:,0],self.Z[:,1],'wo')

View file

@ -6,7 +6,7 @@ import pylab as pb
from ..util.linalg import mdot, jitchol, chol_inv, pdinv from ..util.linalg import mdot, jitchol, chol_inv, pdinv
from ..util.plot import gpplot from ..util.plot import gpplot
from .. import kern from .. import kern
from ..inference.likelihoods import likelihood from ..likelihoods import likelihood
from sparse_GP_regression import sparse_GP_regression from sparse_GP_regression import sparse_GP_regression
class uncollapsed_sparse_GP(sparse_GP_regression): class uncollapsed_sparse_GP(sparse_GP_regression):
@ -136,8 +136,8 @@ class uncollapsed_sparse_GP(sparse_GP_regression):
#dL_dm = np.dot(self.Kmmi,self.psi1V) - np.dot(self.Lambda,self.q_u_mean) #dL_dm = np.dot(self.Kmmi,self.psi1V) - np.dot(self.Lambda,self.q_u_mean)
dL_dm = np.dot(self.Kmmi,self.psi1V) - self.q_u_canonical[0] dL_dm = np.dot(self.Kmmi,self.psi1V) - self.q_u_canonical[0]
#dL_dSim = #dL_dSim =
#dL_dmhSi = #dL_dmhSi =
return np.hstack((dL_dm.flatten(),dL_dmmT_S.flatten())) # natgrad only, grad TODO return np.hstack((dL_dm.flatten(),dL_dmmT_S.flatten())) # natgrad only, grad TODO

View file

@ -154,17 +154,16 @@ class GradientTests(unittest.TestCase):
m.constrain_positive('(linear|bias|white)') m.constrain_positive('(linear|bias|white)')
self.assertTrue(m.checkgrad()) self.assertTrue(m.checkgrad())
def test_GP_EP(self): def test_GP_EP_probit(self):
return # Disabled TODO
N = 20 N = 20
X = np.hstack([np.random.rand(N/2)+1,np.random.rand(N/2)-1])[:,None] X = np.hstack([np.random.normal(5,2,N/2),np.random.normal(10,2,N/2)])[:,None]
k = GPy.kern.rbf(1) + GPy.kern.white(1) Y = np.hstack([np.ones(N/2),np.repeat(-1,N/2)])[:,None]
Y = np.hstack([np.ones(N/2),-np.ones(N/2)])[:,None] kernel = GPy.kern.rbf(1)
likelihood = GPy.inference.likelihoods.probit(Y) distribution = GPy.likelihoods.likelihood_functions.probit()
m = GPy.models.GP_EP(X,likelihood,k) likelihood = GPy.likelihoods.EP(Y, distribution)
m.constrain_positive('(var|len)') m = GPy.models.GP(X, likelihood, kernel)
m.approximate_likelihood() m.ensure_default_constraints()
self.assertTrue(m.checkgrad()) self.assertTrue(m.EPEM)
@unittest.skip("FITC will be broken for a while") @unittest.skip("FITC will be broken for a while")
def test_generalized_FITC(self): def test_generalized_FITC(self):

View file

@ -6,30 +6,26 @@ import Tango
import pylab as pb import pylab as pb
import numpy as np import numpy as np
def gpplot(x,mu,var,edgecol=Tango.coloursHex['darkBlue'],fillcol=Tango.coloursHex['lightBlue'],axes=None,**kwargs): def gpplot(x,mu,lower,upper,edgecol=Tango.coloursHex['darkBlue'],fillcol=Tango.coloursHex['lightBlue'],axes=None,**kwargs):
if axes is None: if axes is None:
axes = pb.gca() axes = pb.gca()
mu = mu.flatten() mu = mu.flatten()
x = x.flatten() x = x.flatten()
lower = lower.flatten()
upper = upper.flatten()
#here's the mean #here's the mean
axes.plot(x,mu,color=edgecol,linewidth=2) axes.plot(x,mu,color=edgecol,linewidth=2)
#ensure variance is a vector #here's the box
if len(var.shape)>1:
err = 2*np.sqrt(np.diag(var))
else:
err = 2*np.sqrt(var)
#here's the 2*std box
kwargs['linewidth']=0.5 kwargs['linewidth']=0.5
if not 'alpha' in kwargs.keys(): if not 'alpha' in kwargs.keys():
kwargs['alpha'] = 0.3 kwargs['alpha'] = 0.3
axes.fill(np.hstack((x,x[::-1])),np.hstack((mu+err,mu[::-1]-err[::-1])),color=fillcol,**kwargs) axes.fill(np.hstack((x,x[::-1])),np.hstack((upper,lower[::-1])),color=fillcol,**kwargs)
#this is the edge: #this is the edge:
axes.plot(x,mu+err,color=edgecol,linewidth=0.2) axes.plot(x,upper,color=edgecol,linewidth=0.2)
axes.plot(x,mu-err,color=edgecol,linewidth=0.2) axes.plot(x,lower,color=edgecol,linewidth=0.2)
def removeRightTicks(ax=None): def removeRightTicks(ax=None):
ax = ax or pb.gca() ax = ax or pb.gca()
@ -74,4 +70,36 @@ def align_subplots(N,M,xlim=None, ylim=None):
else: else:
removeUpperTicks() removeUpperTicks()
def x_frame1D(X,plot_limits=None,resolution=None):
"""
Internal helper function for making plots, returns a set of input values to plot as well as lower and upper limits
"""
assert X.shape[1] ==1, "x_frame1D is defined for one-dimensional inputs"
if plot_limits is None:
xmin,xmax = X.min(0),X.max(0)
xmin, xmax = xmin-0.2*(xmax-xmin), xmax+0.2*(xmax-xmin)
elif len(plot_limits)==2:
xmin, xmax = plot_limits
else:
raise ValueError, "Bad limits for plotting"
Xnew = np.linspace(xmin,xmax,resolution or 200)[:,None]
return Xnew, xmin, xmax
def x_frame2D(X,plot_limits=None,resolution=None):
"""
Internal helper function for making plots, returns a set of input values to plot as well as lower and upper limits
"""
assert X.shape[1] ==2, "x_frame2D is defined for two-dimensional inputs"
if plot_limits is None:
xmin,xmax = X.min(0),X.max(0)
xmin, xmax = xmin-0.2*(xmax-xmin), xmax+0.2*(xmax-xmin)
elif len(plot_limits)==2:
xmin, xmax = plot_limits
else:
raise ValueError, "Bad limits for plotting"
resolution = resolution or 50
xx,yy = np.mgrid[xmin[0]:xmax[0]:1j*resolution,xmin[1]:xmax[1]:1j*resolution]
Xnew = np.vstack((xx.flatten(),yy.flatten())).T
return Xnew, xx, yy, xmin, xmax

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@ -33,6 +33,14 @@ examples Package
:undoc-members: :undoc-members:
:show-inheritance: :show-inheritance:
:mod:`poisson` Module
---------------------
.. automodule:: GPy.examples.poisson
:members:
:undoc-members:
:show-inheritance:
:mod:`regression` Module :mod:`regression` Module
------------------------ ------------------------
@ -57,6 +65,14 @@ examples Package
:undoc-members: :undoc-members:
:show-inheritance: :show-inheritance:
:mod:`sparse_ep_fix` Module
---------------------------
.. automodule:: GPy.examples.sparse_ep_fix
:members:
:undoc-members:
:show-inheritance:
:mod:`uncertain_input_GP_regression_demo` Module :mod:`uncertain_input_GP_regression_demo` Module
------------------------------------------------ ------------------------------------------------

View file

@ -1,22 +1,6 @@
inference Package inference Package
================= =================
:mod:`Expectation_Propagation` Module
-------------------------------------
.. automodule:: GPy.inference.Expectation_Propagation
:members:
:undoc-members:
:show-inheritance:
:mod:`likelihoods` Module
-------------------------
.. automodule:: GPy.inference.likelihoods
:members:
:undoc-members:
:show-inheritance:
:mod:`optimization` Module :mod:`optimization` Module
-------------------------- --------------------------

43
doc/GPy.likelihoods.rst Normal file
View file

@ -0,0 +1,43 @@
likelihoods Package
===================
:mod:`likelihoods` Package
--------------------------
.. automodule:: GPy.likelihoods
:members:
:undoc-members:
:show-inheritance:
:mod:`EP` Module
----------------
.. automodule:: GPy.likelihoods.EP
:members:
:undoc-members:
:show-inheritance:
:mod:`Gaussian` Module
----------------------
.. automodule:: GPy.likelihoods.Gaussian
:members:
:undoc-members:
:show-inheritance:
:mod:`likelihood` Module
------------------------
.. automodule:: GPy.likelihoods.likelihood
:members:
:undoc-members:
:show-inheritance:
:mod:`likelihood_functions` Module
----------------------------------
.. automodule:: GPy.likelihoods.likelihood_functions
:members:
:undoc-members:
:show-inheritance:

View file

@ -17,18 +17,18 @@ models Package
:undoc-members: :undoc-members:
:show-inheritance: :show-inheritance:
:mod:`GPLVM` Module :mod:`GP` Module
------------------- ----------------
.. automodule:: GPy.models.GPLVM .. automodule:: GPy.models.GP
:members: :members:
:undoc-members: :undoc-members:
:show-inheritance: :show-inheritance:
:mod:`GP_EP` Module :mod:`GPLVM` Module
------------------- -------------------
.. automodule:: GPy.models.GP_EP .. automodule:: GPy.models.GPLVM
:members: :members:
:undoc-members: :undoc-members:
:show-inheritance: :show-inheritance:
@ -41,10 +41,10 @@ models Package
:undoc-members: :undoc-members:
:show-inheritance: :show-inheritance:
:mod:`generalized_FITC` Module :mod:`sparse_GP` Module
------------------------------ -----------------------
.. automodule:: GPy.models.generalized_FITC .. automodule:: GPy.models.sparse_GP
:members: :members:
:undoc-members: :undoc-members:
:show-inheritance: :show-inheritance:

View file

@ -18,6 +18,7 @@ Subpackages
GPy.examples GPy.examples
GPy.inference GPy.inference
GPy.kern GPy.kern
GPy.likelihoods
GPy.models GPy.models
GPy.util GPy.util

View file

@ -41,6 +41,7 @@ help:
clean: clean:
-rm -rf $(BUILDDIR)/* -rm -rf $(BUILDDIR)/*
html: html:
$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html $(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
@echo @echo

View file

@ -11,101 +11,49 @@
# All configuration values have a default; values that are commented out # All configuration values have a default; values that are commented out
# serve to show the default. # serve to show the default.
import sys, os import sys
import os
#Mocking uninstalled modules: https://read-the-docs.readthedocs.org/en/latest/faq.html print "python exec:", sys.executable
print "sys.path:", sys.path
#class Mock(object): try:
#__all__ = [] import numpy
#def __init__(self, *args, **kwargs): print "numpy: %s, %s" % (numpy.__version__, numpy.__file__)
#for key, value in kwargs.iteritems(): except ImportError:
#setattr(self, key, value) print "no numpy"
try:
#def __call__(self, *args, **kwargs): import matplotlib
#return Mock() print "matplotlib: %s, %s" % (matplotlib.__version__, matplotlib.__file__)
except ImportError:
#__add__ = __mul__ = __getitem__ = __setitem__ = \ print "no matplotlib"
#__delitem__ = __sub__ = __floordiv__ = __mod__ = __divmod__ = \ try:
#__pow__ = __lshift__ = __rshift__ = __and__ = __xor__ = __or__ = \ import ipython
#__rmul__ = __rsub__ = __rfloordiv__ = __rmod__ = __rdivmod__ = \ print "ipython: %s, %s" % (ipython.__version__, ipython.__file__)
#__rpow__ = __rlshift__ = __rrshift__ = __rand__ = __rxor__ = __ror__ = \ except ImportError:
#__imul__ = __isub__ = __ifloordiv__ = __imod__ = __idivmod__ = \ print "no ipython"
#__ipow__ = __ilshift__ = __irshift__ = __iand__ = __ixor__ = __ior__ = \ try:
#__neg__ = __pos__ = __abs__ = __invert__ = __call__ import sphinx
print "sphinx: %s, %s" % (sphinx.__version__, sphinx.__file__)
#def __getattr__(self, name): except ImportError:
#if name in ('__file__', '__path__'): print "no sphinx"
#return '/dev/null'
#if name == 'sqrt':
#return math.sqrt
#elif name[0] != '_' and name[0] == name[0].upper():
#return type(name, (), {})
#else:
#return Mock(**vars(self))
#def __lt__(self, *args, **kwargs):
#return True
#__nonzero__ = __le__ = __eq__ = __ne__ = __gt__ = __ge__ = __contains__ = \
#__lt__
#def __repr__(self):
## Use _mock_repr to fake the __repr__ call
#res = getattr(self, "_mock_repr")
#return res if isinstance(res, str) else "Mock"
#def __hash__(self):
#return 1
#__len__ = __int__ = __long__ = __index__ = __hash__
#def __oct__(self):
#return '01'
#def __hex__(self):
#return '0x1'
#def __float__(self):
#return 0.1
#def __complex__(self):
#return 1j
#MOCK_MODULES = [
#'pylab', 'scipy', 'matplotlib', 'matplotlib.pyplot', 'pyfits',
#'scipy.constants.constants', 'matplotlib.cm',
#'matplotlib.image', 'matplotlib.colors', 'sunpy.cm',
#'pandas', 'pandas.io', 'pandas.io.parsers',
#'suds', 'matplotlib.ticker', 'matplotlib.colorbar',
#'matplotlib.dates', 'scipy.optimize', 'scipy.ndimage',
#'matplotlib.figure', 'scipy.ndimage.interpolation', 'bs4']
#for mod_name in MOCK_MODULES:
#sys.modules[mod_name] = Mock()
#sys.modules['numpy'] = Mock(pi=math.pi, G=6.67364e-11,
#ndarray=type('ndarray', (), {}),
#dtype=lambda _: Mock(_mock_repr='np.dtype(\'float32\')'))
#sys.modules['scipy.constants'] = Mock(pi=math.pi, G=6.67364e-11)
print "sys.path:", sys.path
# If extensions (or modules to document with autodoc) are in another directory, # If extensions (or modules to document with autodoc) are in another directory,
# add these directories to sys.path here. If the directory is relative to the # add these directories to sys.path here. If the directory is relative to the
# documentation root, use os.path.abspath to make it absolute, like shown here. # documentation root, use os.path.abspath to make it absolute, like shown here.
#sys.path.insert(0, os.path.abspath('..')) #sys.path.insert(0, os.path.abspath('../GPy'))
#print "sys.path.after:", sys.path
print "Adding path"
# If your extensions are in another directory, add it here. If the directory # If your extensions are in another directory, add it here. If the directory
# is relative to the documentation root, use os.path.abspath to make it # is relative to the documentation root, use os.path.abspath to make it
# absolute, like shown here. # absolute, like shown here.
#sys.path.append(os.path.abspath('./sphinxext')) sys.path.append(os.path.abspath('sphinxext'))
# If extensions (or modules to document with autodoc) are in another directory, # If extensions (or modules to document with autodoc) are in another directory,
# add these directories to sys.path here. If the directory is relative to the # add these directories to sys.path here. If the directory is relative to the
# documentation root, use os.path.abspath to make it absolute, like shown here. # documentation root, use os.path.abspath to make it absolute, like shown here.
#sys.path.insert(0, os.path.abspath('.'))
#sys.path.insert(0, os.path.abspath('./sphinxext')) #sys.path.insert(0, os.path.abspath('./sphinxext'))
# -- General configuration ----------------------------------------------------- # -- General configuration -----------------------------------------------------
@ -116,23 +64,24 @@ print "Adding path"
# Add any Sphinx extension module names here, as strings. They can be extensions # Add any Sphinx extension module names here, as strings. They can be extensions
# coming with Sphinx (named 'sphinx.ext.*') or your custom ones. # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
print "Importing extensions" print "Importing extensions"
extensions = [#'ipython_directive', extensions = ['sphinx.ext.autodoc',
'sphinx.ext.autodoc', 'sphinx.ext.viewcode' #'sphinx.ext.doctest'
#'matplotlib.sphinxext.mathmpl', 'sphinx.ext.viewcode',
#'matplotlib.sphinxext.only_directives', 'sphinx.ext.pngmath',
#'matplotlib.sphinxext.plot_directive', 'ipython_directive',
#'ipython_directive' 'ipython_console_highlighting'
] #'matplotlib.sphinxext.plot_directive'
#'sphinx.ext.doctest', ]
#'ipython_console_highlighting', plot_formats = [('png', 80), ('pdf', 50)]
#'inheritance_diagram',
#'numpydoc']
print "finished importing" print "finished importing"
############################################################################## ##############################################################################
## ##
## Mock out imports with C dependencies because ReadTheDocs can't build them. ## Mock out imports with C dependencies because ReadTheDocs can't build them.
#############################################################################
class Mock(object): class Mock(object):
def __init__(self, *args, **kwargs): def __init__(self, *args, **kwargs):
pass pass
@ -151,23 +100,38 @@ class Mock(object):
else: else:
return Mock() return Mock()
#sys.path.append("../GPy")
#import mock #import mock
print "Mocking" print "Mocking"
MOCK_MODULES = ['pylab', 'matplotlib', 'sympy', 'sympy.utilities', 'sympy.utilities.codegen', 'sympy.core.cache', 'sympy.core', 'sympy.parsing', 'sympy.parsing.sympy_parser']#'matplotlib', 'matplotlib.color', 'matplotlib.pyplot', 'pylab' ] MOCK_MODULES = ['pylab', 'sympy', 'sympy.utilities', 'sympy.utilities.codegen', 'sympy.core.cache', 'sympy.core', 'sympy.parsing', 'sympy.parsing.sympy_parser', 'matplotlib']
#'matplotlib', 'matplotlib.color', 'matplotlib.pyplot', 'pylab' ]
for mod_name in MOCK_MODULES: for mod_name in MOCK_MODULES:
sys.modules[mod_name] = Mock() sys.modules[mod_name] = Mock()
# ----------------------- READTHEDOCS ------------------ # ----------------------- READTHEDOCS ------------------
on_rtd = os.environ.get('READTHEDOCS', None) == 'True' on_rtd = os.environ.get('READTHEDOCS', None) == 'True'
on_rtd = True
if on_rtd: if on_rtd:
sys.path.append("../GPy") sys.path.append(os.path.abspath('../GPy'))
os.system("pwd")
os.system("sphinx-apidoc -f -o . ../GPy") import subprocess
#os.system("cd ..")
#os.system("cd ./docs") proc = subprocess.Popen("pwd", stdout=subprocess.PIPE, shell=True)
(out, err) = proc.communicate()
print "program output:", out
proc = subprocess.Popen("ls ../", stdout=subprocess.PIPE, shell=True)
(out, err) = proc.communicate()
print "program output:", out
proc = subprocess.Popen("sphinx-apidoc -f -o . ../GPy", stdout=subprocess.PIPE, shell=True)
(out, err) = proc.communicate()
print "program output:", out
#proc = subprocess.Popen("whereis numpy", stdout=subprocess.PIPE, shell=True)
#(out, err) = proc.communicate()
#print "program output:", out
#proc = subprocess.Popen("whereis matplotlib", stdout=subprocess.PIPE, shell=True)
#(out, err) = proc.communicate()
#print "program output:", out
print "Compiled files" print "Compiled files"
@ -317,21 +281,21 @@ htmlhelp_basename = 'GPydoc'
# -- Options for LaTeX output -------------------------------------------------- # -- Options for LaTeX output --------------------------------------------------
latex_elements = { latex_elements = {
# The paper size ('letterpaper' or 'a4paper'). # The paper size ('letterpaper' or 'a4paper').
#'papersize': 'letterpaper', #'papersize': 'letterpaper',
# The font size ('10pt', '11pt' or '12pt'). # The font size ('10pt', '11pt' or '12pt').
#'pointsize': '10pt', #'pointsize': '10pt',
# Additional stuff for the LaTeX preamble. # Additional stuff for the LaTeX preamble.
#'preamble': '', #'preamble': '',
} }
# Grouping the document tree into LaTeX files. List of tuples # Grouping the document tree into LaTeX files. List of tuples
# (source start file, target name, title, author, documentclass [howto/manual]). # (source start file, target name, title, author, documentclass [howto/manual]).
latex_documents = [ latex_documents = [
('index', 'GPy.tex', u'GPy Documentation', ('index', 'GPy.tex', u'GPy Documentation',
u'Author', 'manual'), u'Author', 'manual'),
] ]
# The name of an image file (relative to this directory) to place at the top of # The name of an image file (relative to this directory) to place at the top of
@ -374,9 +338,9 @@ man_pages = [
# (source start file, target name, title, author, # (source start file, target name, title, author,
# dir menu entry, description, category) # dir menu entry, description, category)
texinfo_documents = [ texinfo_documents = [
('index', 'GPy', u'GPy Documentation', ('index', 'GPy', u'GPy Documentation',
u'Author', 'GPy', 'One line description of project.', u'Author', 'GPy', 'One line description of project.',
'Miscellaneous'), 'Miscellaneous'),
] ]
# Documents to append as an appendix to all manuals. # Documents to append as an appendix to all manuals.
@ -431,17 +395,4 @@ epub_copyright = u'2013, Author'
# Allow duplicate toc entries. # Allow duplicate toc entries.
#epub_tocdup = True #epub_tocdup = True
############################################################################# autodoc_member_order = "source"
#
# Include constructors in all the docs
# Got this method from:
# http://stackoverflow.com/questions/5599254/how-to-use-sphinxs-autodoc-to-document-a-classs-init-self-method
#def skip(app, what, name, obj, skip, options):
#if name == "__init__":
#return False
#return skip
#def setup(app):
#app.connect("autodoc-skip-member", skip)

3
doc/doc-requirements.txt Normal file
View file

@ -0,0 +1,3 @@
ipython
numpy
scipy

View file

@ -8,8 +8,8 @@ Welcome to GPy's documentation!
For a quick start, you can have a look at one of the tutorials: For a quick start, you can have a look at one of the tutorials:
* `Basic Gaussian process regression <tuto_GP_regression.html>`_ * `Basic Gaussian process regression <tuto_GP_regression.html>`_
* `A kernel overview <tuto_kernel_overview.html>`_
* Advanced GP regression (Forthcoming) * Advanced GP regression (Forthcoming)
* Kernel manipulation (Forthcoming)
* Writting kernels (Forthcoming) * Writting kernels (Forthcoming)
You may also be interested by some examples in the GPy/examples folder. You may also be interested by some examples in the GPy/examples folder.
@ -28,4 +28,3 @@ Indices and tables
* :ref:`genindex` * :ref:`genindex`
* :ref:`modindex` * :ref:`modindex`
* :ref:`search` * :ref:`search`

File diff suppressed because it is too large Load diff

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@ -1,2 +0,0 @@
from __future__ import print_function

View file

@ -1,427 +0,0 @@
"""Attempt to generate templates for module reference with Sphinx
XXX - we exclude extension modules
To include extension modules, first identify them as valid in the
``_uri2path`` method, then handle them in the ``_parse_module`` script.
We get functions and classes by parsing the text of .py files.
Alternatively we could import the modules for discovery, and we'd have
to do that for extension modules. This would involve changing the
``_parse_module`` method to work via import and introspection, and
might involve changing ``discover_modules`` (which determines which
files are modules, and therefore which module URIs will be passed to
``_parse_module``).
NOTE: this is a modified version of a script originally shipped with the
PyMVPA project, which we've adapted for NIPY use. PyMVPA is an MIT-licensed
project."""
# Stdlib imports
import os
import re
# Functions and classes
class ApiDocWriter(object):
''' Class for automatic detection and parsing of API docs
to Sphinx-parsable reST format'''
# only separating first two levels
rst_section_levels = ['*', '=', '-', '~', '^']
def __init__(self,
package_name,
rst_extension='.rst',
package_skip_patterns=None,
module_skip_patterns=None,
):
''' Initialize package for parsing
Parameters
----------
package_name : string
Name of the top-level package. *package_name* must be the
name of an importable package
rst_extension : string, optional
Extension for reST files, default '.rst'
package_skip_patterns : None or sequence of {strings, regexps}
Sequence of strings giving URIs of packages to be excluded
Operates on the package path, starting at (including) the
first dot in the package path, after *package_name* - so,
if *package_name* is ``sphinx``, then ``sphinx.util`` will
result in ``.util`` being passed for earching by these
regexps. If is None, gives default. Default is:
['\.tests$']
module_skip_patterns : None or sequence
Sequence of strings giving URIs of modules to be excluded
Operates on the module name including preceding URI path,
back to the first dot after *package_name*. For example
``sphinx.util.console`` results in the string to search of
``.util.console``
If is None, gives default. Default is:
['\.setup$', '\._']
'''
if package_skip_patterns is None:
package_skip_patterns = ['\\.tests$']
if module_skip_patterns is None:
module_skip_patterns = ['\\.setup$', '\\._']
self.package_name = package_name
self.rst_extension = rst_extension
self.package_skip_patterns = package_skip_patterns
self.module_skip_patterns = module_skip_patterns
def get_package_name(self):
return self._package_name
def set_package_name(self, package_name):
''' Set package_name
>>> docwriter = ApiDocWriter('sphinx')
>>> import sphinx
>>> docwriter.root_path == sphinx.__path__[0]
True
>>> docwriter.package_name = 'docutils'
>>> import docutils
>>> docwriter.root_path == docutils.__path__[0]
True
'''
# It's also possible to imagine caching the module parsing here
self._package_name = package_name
self.root_module = __import__(package_name)
self.root_path = self.root_module.__path__[0]
self.written_modules = None
package_name = property(get_package_name, set_package_name, None,
'get/set package_name')
def _get_object_name(self, line):
''' Get second token in line
>>> docwriter = ApiDocWriter('sphinx')
>>> docwriter._get_object_name(" def func(): ")
'func'
>>> docwriter._get_object_name(" class Klass(object): ")
'Klass'
>>> docwriter._get_object_name(" class Klass: ")
'Klass'
'''
name = line.split()[1].split('(')[0].strip()
# in case we have classes which are not derived from object
# ie. old style classes
return name.rstrip(':')
def _uri2path(self, uri):
''' Convert uri to absolute filepath
Parameters
----------
uri : string
URI of python module to return path for
Returns
-------
path : None or string
Returns None if there is no valid path for this URI
Otherwise returns absolute file system path for URI
Examples
--------
>>> docwriter = ApiDocWriter('sphinx')
>>> import sphinx
>>> modpath = sphinx.__path__[0]
>>> res = docwriter._uri2path('sphinx.builder')
>>> res == os.path.join(modpath, 'builder.py')
True
>>> res = docwriter._uri2path('sphinx')
>>> res == os.path.join(modpath, '__init__.py')
True
>>> docwriter._uri2path('sphinx.does_not_exist')
'''
if uri == self.package_name:
return os.path.join(self.root_path, '__init__.py')
path = uri.replace('.', os.path.sep)
path = path.replace(self.package_name + os.path.sep, '')
path = os.path.join(self.root_path, path)
# XXX maybe check for extensions as well?
if os.path.exists(path + '.py'): # file
path += '.py'
elif os.path.exists(os.path.join(path, '__init__.py')):
path = os.path.join(path, '__init__.py')
else:
return None
return path
def _path2uri(self, dirpath):
''' Convert directory path to uri '''
relpath = dirpath.replace(self.root_path, self.package_name)
if relpath.startswith(os.path.sep):
relpath = relpath[1:]
return relpath.replace(os.path.sep, '.')
def _parse_module(self, uri):
''' Parse module defined in *uri* '''
filename = self._uri2path(uri)
if filename is None:
# nothing that we could handle here.
return ([],[])
f = open(filename, 'rt')
functions, classes = self._parse_lines(f)
f.close()
return functions, classes
def _parse_lines(self, linesource):
''' Parse lines of text for functions and classes '''
functions = []
classes = []
for line in linesource:
if line.startswith('def ') and line.count('('):
# exclude private stuff
name = self._get_object_name(line)
if not name.startswith('_'):
functions.append(name)
elif line.startswith('class '):
# exclude private stuff
name = self._get_object_name(line)
if not name.startswith('_'):
classes.append(name)
else:
pass
functions.sort()
classes.sort()
return functions, classes
def generate_api_doc(self, uri):
'''Make autodoc documentation template string for a module
Parameters
----------
uri : string
python location of module - e.g 'sphinx.builder'
Returns
-------
S : string
Contents of API doc
'''
# get the names of all classes and functions
functions, classes = self._parse_module(uri)
if not len(functions) and not len(classes):
print 'WARNING: Empty -',uri # dbg
return ''
# Make a shorter version of the uri that omits the package name for
# titles
uri_short = re.sub(r'^%s\.' % self.package_name,'',uri)
ad = '.. AUTO-GENERATED FILE -- DO NOT EDIT!\n\n'
chap_title = uri_short
ad += (chap_title+'\n'+ self.rst_section_levels[1] * len(chap_title)
+ '\n\n')
# Set the chapter title to read 'module' for all modules except for the
# main packages
if '.' in uri:
title = 'Module: :mod:`' + uri_short + '`'
else:
title = ':mod:`' + uri_short + '`'
ad += title + '\n' + self.rst_section_levels[2] * len(title)
if len(classes):
ad += '\nInheritance diagram for ``%s``:\n\n' % uri
ad += '.. inheritance-diagram:: %s \n' % uri
ad += ' :parts: 3\n'
ad += '\n.. automodule:: ' + uri + '\n'
ad += '\n.. currentmodule:: ' + uri + '\n'
multi_class = len(classes) > 1
multi_fx = len(functions) > 1
if multi_class:
ad += '\n' + 'Classes' + '\n' + \
self.rst_section_levels[2] * 7 + '\n'
elif len(classes) and multi_fx:
ad += '\n' + 'Class' + '\n' + \
self.rst_section_levels[2] * 5 + '\n'
for c in classes:
ad += '\n:class:`' + c + '`\n' \
+ self.rst_section_levels[multi_class + 2 ] * \
(len(c)+9) + '\n\n'
ad += '\n.. autoclass:: ' + c + '\n'
# must NOT exclude from index to keep cross-refs working
ad += ' :members:\n' \
' :undoc-members:\n' \
' :show-inheritance:\n' \
' :inherited-members:\n' \
'\n' \
' .. automethod:: __init__\n'
if multi_fx:
ad += '\n' + 'Functions' + '\n' + \
self.rst_section_levels[2] * 9 + '\n\n'
elif len(functions) and multi_class:
ad += '\n' + 'Function' + '\n' + \
self.rst_section_levels[2] * 8 + '\n\n'
for f in functions:
# must NOT exclude from index to keep cross-refs working
ad += '\n.. autofunction:: ' + uri + '.' + f + '\n\n'
return ad
def _survives_exclude(self, matchstr, match_type):
''' Returns True if *matchstr* does not match patterns
``self.package_name`` removed from front of string if present
Examples
--------
>>> dw = ApiDocWriter('sphinx')
>>> dw._survives_exclude('sphinx.okpkg', 'package')
True
>>> dw.package_skip_patterns.append('^\\.badpkg$')
>>> dw._survives_exclude('sphinx.badpkg', 'package')
False
>>> dw._survives_exclude('sphinx.badpkg', 'module')
True
>>> dw._survives_exclude('sphinx.badmod', 'module')
True
>>> dw.module_skip_patterns.append('^\\.badmod$')
>>> dw._survives_exclude('sphinx.badmod', 'module')
False
'''
if match_type == 'module':
patterns = self.module_skip_patterns
elif match_type == 'package':
patterns = self.package_skip_patterns
else:
raise ValueError('Cannot interpret match type "%s"'
% match_type)
# Match to URI without package name
L = len(self.package_name)
if matchstr[:L] == self.package_name:
matchstr = matchstr[L:]
for pat in patterns:
try:
pat.search
except AttributeError:
pat = re.compile(pat)
if pat.search(matchstr):
return False
return True
def discover_modules(self):
''' Return module sequence discovered from ``self.package_name``
Parameters
----------
None
Returns
-------
mods : sequence
Sequence of module names within ``self.package_name``
Examples
--------
>>> dw = ApiDocWriter('sphinx')
>>> mods = dw.discover_modules()
>>> 'sphinx.util' in mods
True
>>> dw.package_skip_patterns.append('\.util$')
>>> 'sphinx.util' in dw.discover_modules()
False
>>>
'''
modules = [self.package_name]
# raw directory parsing
for dirpath, dirnames, filenames in os.walk(self.root_path):
# Check directory names for packages
root_uri = self._path2uri(os.path.join(self.root_path,
dirpath))
for dirname in dirnames[:]: # copy list - we modify inplace
package_uri = '.'.join((root_uri, dirname))
if (self._uri2path(package_uri) and
self._survives_exclude(package_uri, 'package')):
modules.append(package_uri)
else:
dirnames.remove(dirname)
# Check filenames for modules
for filename in filenames:
module_name = filename[:-3]
module_uri = '.'.join((root_uri, module_name))
if (self._uri2path(module_uri) and
self._survives_exclude(module_uri, 'module')):
modules.append(module_uri)
return sorted(modules)
def write_modules_api(self, modules,outdir):
# write the list
written_modules = []
for m in modules:
api_str = self.generate_api_doc(m)
if not api_str:
continue
# write out to file
outfile = os.path.join(outdir,
m + self.rst_extension)
fileobj = open(outfile, 'wt')
fileobj.write(api_str)
fileobj.close()
written_modules.append(m)
self.written_modules = written_modules
def write_api_docs(self, outdir):
"""Generate API reST files.
Parameters
----------
outdir : string
Directory name in which to store files
We create automatic filenames for each module
Returns
-------
None
Notes
-----
Sets self.written_modules to list of written modules
"""
if not os.path.exists(outdir):
os.mkdir(outdir)
# compose list of modules
modules = self.discover_modules()
self.write_modules_api(modules,outdir)
def write_index(self, outdir, froot='gen', relative_to=None):
"""Make a reST API index file from written files
Parameters
----------
path : string
Filename to write index to
outdir : string
Directory to which to write generated index file
froot : string, optional
root (filename without extension) of filename to write to
Defaults to 'gen'. We add ``self.rst_extension``.
relative_to : string
path to which written filenames are relative. This
component of the written file path will be removed from
outdir, in the generated index. Default is None, meaning,
leave path as it is.
"""
if self.written_modules is None:
raise ValueError('No modules written')
# Get full filename path
path = os.path.join(outdir, froot+self.rst_extension)
# Path written into index is relative to rootpath
if relative_to is not None:
relpath = outdir.replace(relative_to + os.path.sep, '')
else:
relpath = outdir
idx = open(path,'wt')
w = idx.write
w('.. AUTO-GENERATED FILE -- DO NOT EDIT!\n\n')
w('.. toctree::\n\n')
for f in self.written_modules:
w(' %s\n' % os.path.join(relpath,f))
idx.close()

View file

@ -1,497 +0,0 @@
"""Extract reference documentation from the NumPy source tree.
"""
import inspect
import textwrap
import re
import pydoc
from StringIO import StringIO
from warnings import warn
4
class Reader(object):
"""A line-based string reader.
"""
def __init__(self, data):
"""
Parameters
----------
data : str
String with lines separated by '\n'.
"""
if isinstance(data,list):
self._str = data
else:
self._str = data.split('\n') # store string as list of lines
self.reset()
def __getitem__(self, n):
return self._str[n]
def reset(self):
self._l = 0 # current line nr
def read(self):
if not self.eof():
out = self[self._l]
self._l += 1
return out
else:
return ''
def seek_next_non_empty_line(self):
for l in self[self._l:]:
if l.strip():
break
else:
self._l += 1
def eof(self):
return self._l >= len(self._str)
def read_to_condition(self, condition_func):
start = self._l
for line in self[start:]:
if condition_func(line):
return self[start:self._l]
self._l += 1
if self.eof():
return self[start:self._l+1]
return []
def read_to_next_empty_line(self):
self.seek_next_non_empty_line()
def is_empty(line):
return not line.strip()
return self.read_to_condition(is_empty)
def read_to_next_unindented_line(self):
def is_unindented(line):
return (line.strip() and (len(line.lstrip()) == len(line)))
return self.read_to_condition(is_unindented)
def peek(self,n=0):
if self._l + n < len(self._str):
return self[self._l + n]
else:
return ''
def is_empty(self):
return not ''.join(self._str).strip()
class NumpyDocString(object):
def __init__(self,docstring):
docstring = textwrap.dedent(docstring).split('\n')
self._doc = Reader(docstring)
self._parsed_data = {
'Signature': '',
'Summary': [''],
'Extended Summary': [],
'Parameters': [],
'Returns': [],
'Raises': [],
'Warns': [],
'Other Parameters': [],
'Attributes': [],
'Methods': [],
'See Also': [],
'Notes': [],
'Warnings': [],
'References': '',
'Examples': '',
'index': {}
}
self._parse()
def __getitem__(self,key):
return self._parsed_data[key]
def __setitem__(self,key,val):
if not self._parsed_data.has_key(key):
warn("Unknown section %s" % key)
else:
self._parsed_data[key] = val
def _is_at_section(self):
self._doc.seek_next_non_empty_line()
if self._doc.eof():
return False
l1 = self._doc.peek().strip() # e.g. Parameters
if l1.startswith('.. index::'):
return True
l2 = self._doc.peek(1).strip() # ---------- or ==========
return l2.startswith('-'*len(l1)) or l2.startswith('='*len(l1))
def _strip(self,doc):
i = 0
j = 0
for i,line in enumerate(doc):
if line.strip(): break
for j,line in enumerate(doc[::-1]):
if line.strip(): break
return doc[i:len(doc)-j]
def _read_to_next_section(self):
section = self._doc.read_to_next_empty_line()
while not self._is_at_section() and not self._doc.eof():
if not self._doc.peek(-1).strip(): # previous line was empty
section += ['']
section += self._doc.read_to_next_empty_line()
return section
def _read_sections(self):
while not self._doc.eof():
data = self._read_to_next_section()
name = data[0].strip()
if name.startswith('..'): # index section
yield name, data[1:]
elif len(data) < 2:
yield StopIteration
else:
yield name, self._strip(data[2:])
def _parse_param_list(self,content):
r = Reader(content)
params = []
while not r.eof():
header = r.read().strip()
if ' : ' in header:
arg_name, arg_type = header.split(' : ')[:2]
else:
arg_name, arg_type = header, ''
desc = r.read_to_next_unindented_line()
desc = dedent_lines(desc)
params.append((arg_name,arg_type,desc))
return params
_name_rgx = re.compile(r"^\s*(:(?P<role>\w+):`(?P<name>[a-zA-Z0-9_.-]+)`|"
r" (?P<name2>[a-zA-Z0-9_.-]+))\s*", re.X)
def _parse_see_also(self, content):
"""
func_name : Descriptive text
continued text
another_func_name : Descriptive text
func_name1, func_name2, :meth:`func_name`, func_name3
"""
items = []
def parse_item_name(text):
"""Match ':role:`name`' or 'name'"""
m = self._name_rgx.match(text)
if m:
g = m.groups()
if g[1] is None:
return g[3], None
else:
return g[2], g[1]
raise ValueError("%s is not a item name" % text)
def push_item(name, rest):
if not name:
return
name, role = parse_item_name(name)
items.append((name, list(rest), role))
del rest[:]
current_func = None
rest = []
for line in content:
if not line.strip(): continue
m = self._name_rgx.match(line)
if m and line[m.end():].strip().startswith(':'):
push_item(current_func, rest)
current_func, line = line[:m.end()], line[m.end():]
rest = [line.split(':', 1)[1].strip()]
if not rest[0]:
rest = []
elif not line.startswith(' '):
push_item(current_func, rest)
current_func = None
if ',' in line:
for func in line.split(','):
push_item(func, [])
elif line.strip():
current_func = line
elif current_func is not None:
rest.append(line.strip())
push_item(current_func, rest)
return items
def _parse_index(self, section, content):
"""
.. index: default
:refguide: something, else, and more
"""
def strip_each_in(lst):
return [s.strip() for s in lst]
out = {}
section = section.split('::')
if len(section) > 1:
out['default'] = strip_each_in(section[1].split(','))[0]
for line in content:
line = line.split(':')
if len(line) > 2:
out[line[1]] = strip_each_in(line[2].split(','))
return out
def _parse_summary(self):
"""Grab signature (if given) and summary"""
if self._is_at_section():
return
summary = self._doc.read_to_next_empty_line()
summary_str = " ".join([s.strip() for s in summary]).strip()
if re.compile('^([\w., ]+=)?\s*[\w\.]+\(.*\)$').match(summary_str):
self['Signature'] = summary_str
if not self._is_at_section():
self['Summary'] = self._doc.read_to_next_empty_line()
else:
self['Summary'] = summary
if not self._is_at_section():
self['Extended Summary'] = self._read_to_next_section()
def _parse(self):
self._doc.reset()
self._parse_summary()
for (section,content) in self._read_sections():
if not section.startswith('..'):
section = ' '.join([s.capitalize() for s in section.split(' ')])
if section in ('Parameters', 'Attributes', 'Methods',
'Returns', 'Raises', 'Warns'):
self[section] = self._parse_param_list(content)
elif section.startswith('.. index::'):
self['index'] = self._parse_index(section, content)
elif section == 'See Also':
self['See Also'] = self._parse_see_also(content)
else:
self[section] = content
# string conversion routines
def _str_header(self, name, symbol='-'):
return [name, len(name)*symbol]
def _str_indent(self, doc, indent=4):
out = []
for line in doc:
out += [' '*indent + line]
return out
def _str_signature(self):
if self['Signature']:
return [self['Signature'].replace('*','\*')] + ['']
else:
return ['']
def _str_summary(self):
if self['Summary']:
return self['Summary'] + ['']
else:
return []
def _str_extended_summary(self):
if self['Extended Summary']:
return self['Extended Summary'] + ['']
else:
return []
def _str_param_list(self, name):
out = []
if self[name]:
out += self._str_header(name)
for param,param_type,desc in self[name]:
out += ['%s : %s' % (param, param_type)]
out += self._str_indent(desc)
out += ['']
return out
def _str_section(self, name):
out = []
if self[name]:
out += self._str_header(name)
out += self[name]
out += ['']
return out
def _str_see_also(self, func_role):
if not self['See Also']: return []
out = []
out += self._str_header("See Also")
last_had_desc = True
for func, desc, role in self['See Also']:
if role:
link = ':%s:`%s`' % (role, func)
elif func_role:
link = ':%s:`%s`' % (func_role, func)
else:
link = "`%s`_" % func
if desc or last_had_desc:
out += ['']
out += [link]
else:
out[-1] += ", %s" % link
if desc:
out += self._str_indent([' '.join(desc)])
last_had_desc = True
else:
last_had_desc = False
out += ['']
return out
def _str_index(self):
idx = self['index']
out = []
out += ['.. index:: %s' % idx.get('default','')]
for section, references in idx.iteritems():
if section == 'default':
continue
out += [' :%s: %s' % (section, ', '.join(references))]
return out
def __str__(self, func_role=''):
out = []
out += self._str_signature()
out += self._str_summary()
out += self._str_extended_summary()
for param_list in ('Parameters','Returns','Raises'):
out += self._str_param_list(param_list)
out += self._str_section('Warnings')
out += self._str_see_also(func_role)
for s in ('Notes','References','Examples'):
out += self._str_section(s)
out += self._str_index()
return '\n'.join(out)
def indent(str,indent=4):
indent_str = ' '*indent
if str is None:
return indent_str
lines = str.split('\n')
return '\n'.join(indent_str + l for l in lines)
def dedent_lines(lines):
"""Deindent a list of lines maximally"""
return textwrap.dedent("\n".join(lines)).split("\n")
def header(text, style='-'):
return text + '\n' + style*len(text) + '\n'
class FunctionDoc(NumpyDocString):
def __init__(self, func, role='func', doc=None):
self._f = func
self._role = role # e.g. "func" or "meth"
if doc is None:
doc = inspect.getdoc(func) or ''
try:
NumpyDocString.__init__(self, doc)
except ValueError, e:
print '*'*78
print "ERROR: '%s' while parsing `%s`" % (e, self._f)
print '*'*78
#print "Docstring follows:"
#print doclines
#print '='*78
if not self['Signature']:
func, func_name = self.get_func()
try:
# try to read signature
argspec = inspect.getargspec(func)
argspec = inspect.formatargspec(*argspec)
argspec = argspec.replace('*','\*')
signature = '%s%s' % (func_name, argspec)
except TypeError, e:
signature = '%s()' % func_name
self['Signature'] = signature
def get_func(self):
func_name = getattr(self._f, '__name__', self.__class__.__name__)
if inspect.isclass(self._f):
func = getattr(self._f, '__call__', self._f.__init__)
else:
func = self._f
return func, func_name
def __str__(self):
out = ''
func, func_name = self.get_func()
signature = self['Signature'].replace('*', '\*')
roles = {'func': 'function',
'meth': 'method'}
if self._role:
if not roles.has_key(self._role):
print "Warning: invalid role %s" % self._role
out += '.. %s:: %s\n \n\n' % (roles.get(self._role,''),
func_name)
out += super(FunctionDoc, self).__str__(func_role=self._role)
return out
class ClassDoc(NumpyDocString):
def __init__(self,cls,modulename='',func_doc=FunctionDoc,doc=None):
if not inspect.isclass(cls):
raise ValueError("Initialise using a class. Got %r" % cls)
self._cls = cls
if modulename and not modulename.endswith('.'):
modulename += '.'
self._mod = modulename
self._name = cls.__name__
self._func_doc = func_doc
if doc is None:
doc = pydoc.getdoc(cls)
NumpyDocString.__init__(self, doc)
@property
def methods(self):
return [name for name,func in inspect.getmembers(self._cls)
if not name.startswith('_') and callable(func)]
def __str__(self):
out = ''
out += super(ClassDoc, self).__str__()
out += "\n\n"
#for m in self.methods:
# print "Parsing `%s`" % m
# out += str(self._func_doc(getattr(self._cls,m), 'meth')) + '\n\n'
# out += '.. index::\n single: %s; %s\n\n' % (self._name, m)
return out

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@ -1,136 +0,0 @@
import re, inspect, textwrap, pydoc
from docscrape import NumpyDocString, FunctionDoc, ClassDoc
class SphinxDocString(NumpyDocString):
# string conversion routines
def _str_header(self, name, symbol='`'):
return ['.. rubric:: ' + name, '']
def _str_field_list(self, name):
return [':' + name + ':']
def _str_indent(self, doc, indent=4):
out = []
for line in doc:
out += [' '*indent + line]
return out
def _str_signature(self):
return ['']
if self['Signature']:
return ['``%s``' % self['Signature']] + ['']
else:
return ['']
def _str_summary(self):
return self['Summary'] + ['']
def _str_extended_summary(self):
return self['Extended Summary'] + ['']
def _str_param_list(self, name):
out = []
if self[name]:
out += self._str_field_list(name)
out += ['']
for param,param_type,desc in self[name]:
out += self._str_indent(['**%s** : %s' % (param.strip(),
param_type)])
out += ['']
out += self._str_indent(desc,8)
out += ['']
return out
def _str_section(self, name):
out = []
if self[name]:
out += self._str_header(name)
out += ['']
content = textwrap.dedent("\n".join(self[name])).split("\n")
out += content
out += ['']
return out
def _str_see_also(self, func_role):
out = []
if self['See Also']:
see_also = super(SphinxDocString, self)._str_see_also(func_role)
out = ['.. seealso::', '']
out += self._str_indent(see_also[2:])
return out
def _str_warnings(self):
out = []
if self['Warnings']:
out = ['.. warning::', '']
out += self._str_indent(self['Warnings'])
return out
def _str_index(self):
idx = self['index']
out = []
if len(idx) == 0:
return out
out += ['.. index:: %s' % idx.get('default','')]
for section, references in idx.iteritems():
if section == 'default':
continue
elif section == 'refguide':
out += [' single: %s' % (', '.join(references))]
else:
out += [' %s: %s' % (section, ','.join(references))]
return out
def _str_references(self):
out = []
if self['References']:
out += self._str_header('References')
if isinstance(self['References'], str):
self['References'] = [self['References']]
out.extend(self['References'])
out += ['']
return out
def __str__(self, indent=0, func_role="obj"):
out = []
out += self._str_signature()
out += self._str_index() + ['']
out += self._str_summary()
out += self._str_extended_summary()
for param_list in ('Parameters', 'Attributes', 'Methods',
'Returns','Raises'):
out += self._str_param_list(param_list)
out += self._str_warnings()
out += self._str_see_also(func_role)
out += self._str_section('Notes')
out += self._str_references()
out += self._str_section('Examples')
out = self._str_indent(out,indent)
return '\n'.join(out)
class SphinxFunctionDoc(SphinxDocString, FunctionDoc):
pass
class SphinxClassDoc(SphinxDocString, ClassDoc):
pass
def get_doc_object(obj, what=None, doc=None):
if what is None:
if inspect.isclass(obj):
what = 'class'
elif inspect.ismodule(obj):
what = 'module'
elif callable(obj):
what = 'function'
else:
what = 'object'
if what == 'class':
return SphinxClassDoc(obj, '', func_doc=SphinxFunctionDoc, doc=doc)
elif what in ('function', 'method'):
return SphinxFunctionDoc(obj, '', doc=doc)
else:
if doc is None:
doc = pydoc.getdoc(obj)
return SphinxDocString(doc)

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@ -1,407 +0,0 @@
"""
Defines a docutils directive for inserting inheritance diagrams.
Provide the directive with one or more classes or modules (separated
by whitespace). For modules, all of the classes in that module will
be used.
Example::
Given the following classes:
class A: pass
class B(A): pass
class C(A): pass
class D(B, C): pass
class E(B): pass
.. inheritance-diagram: D E
Produces a graph like the following:
A
/ \
B C
/ \ /
E D
The graph is inserted as a PNG+image map into HTML and a PDF in
LaTeX.
"""
import inspect
import os
import re
import subprocess
try:
from hashlib import md5
except ImportError:
from md5 import md5
from docutils.nodes import Body, Element
from docutils.parsers.rst import directives
from sphinx.roles import xfileref_role
def my_import(name):
"""Module importer - taken from the python documentation.
This function allows importing names with dots in them."""
mod = __import__(name)
components = name.split('.')
for comp in components[1:]:
mod = getattr(mod, comp)
return mod
class DotException(Exception):
pass
class InheritanceGraph(object):
"""
Given a list of classes, determines the set of classes that
they inherit from all the way to the root "object", and then
is able to generate a graphviz dot graph from them.
"""
def __init__(self, class_names, show_builtins=False):
"""
*class_names* is a list of child classes to show bases from.
If *show_builtins* is True, then Python builtins will be shown
in the graph.
"""
self.class_names = class_names
self.classes = self._import_classes(class_names)
self.all_classes = self._all_classes(self.classes)
if len(self.all_classes) == 0:
raise ValueError("No classes found for inheritance diagram")
self.show_builtins = show_builtins
py_sig_re = re.compile(r'''^([\w.]*\.)? # class names
(\w+) \s* $ # optionally arguments
''', re.VERBOSE)
def _import_class_or_module(self, name):
"""
Import a class using its fully-qualified *name*.
"""
try:
path, base = self.py_sig_re.match(name).groups()
except:
raise ValueError(
"Invalid class or module '%s' specified for inheritance diagram" % name)
fullname = (path or '') + base
path = (path and path.rstrip('.'))
if not path:
path = base
try:
module = __import__(path, None, None, [])
# We must do an import of the fully qualified name. Otherwise if a
# subpackage 'a.b' is requested where 'import a' does NOT provide
# 'a.b' automatically, then 'a.b' will not be found below. This
# second call will force the equivalent of 'import a.b' to happen
# after the top-level import above.
my_import(fullname)
except ImportError:
raise ValueError(
"Could not import class or module '%s' specified for inheritance diagram" % name)
try:
todoc = module
for comp in fullname.split('.')[1:]:
todoc = getattr(todoc, comp)
except AttributeError:
raise ValueError(
"Could not find class or module '%s' specified for inheritance diagram" % name)
# If a class, just return it
if inspect.isclass(todoc):
return [todoc]
elif inspect.ismodule(todoc):
classes = []
for cls in todoc.__dict__.values():
if inspect.isclass(cls) and cls.__module__ == todoc.__name__:
classes.append(cls)
return classes
raise ValueError(
"'%s' does not resolve to a class or module" % name)
def _import_classes(self, class_names):
"""
Import a list of classes.
"""
classes = []
for name in class_names:
classes.extend(self._import_class_or_module(name))
return classes
def _all_classes(self, classes):
"""
Return a list of all classes that are ancestors of *classes*.
"""
all_classes = {}
def recurse(cls):
all_classes[cls] = None
for c in cls.__bases__:
if c not in all_classes:
recurse(c)
for cls in classes:
recurse(cls)
return all_classes.keys()
def class_name(self, cls, parts=0):
"""
Given a class object, return a fully-qualified name. This
works for things I've tested in matplotlib so far, but may not
be completely general.
"""
module = cls.__module__
if module == '__builtin__':
fullname = cls.__name__
else:
fullname = "%s.%s" % (module, cls.__name__)
if parts == 0:
return fullname
name_parts = fullname.split('.')
return '.'.join(name_parts[-parts:])
def get_all_class_names(self):
"""
Get all of the class names involved in the graph.
"""
return [self.class_name(x) for x in self.all_classes]
# These are the default options for graphviz
default_graph_options = {
"rankdir": "LR",
"size": '"8.0, 12.0"'
}
default_node_options = {
"shape": "box",
"fontsize": 10,
"height": 0.25,
"fontname": "Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",
"style": '"setlinewidth(0.5)"'
}
default_edge_options = {
"arrowsize": 0.5,
"style": '"setlinewidth(0.5)"'
}
def _format_node_options(self, options):
return ','.join(["%s=%s" % x for x in options.items()])
def _format_graph_options(self, options):
return ''.join(["%s=%s;\n" % x for x in options.items()])
def generate_dot(self, fd, name, parts=0, urls={},
graph_options={}, node_options={},
edge_options={}):
"""
Generate a graphviz dot graph from the classes that
were passed in to __init__.
*fd* is a Python file-like object to write to.
*name* is the name of the graph
*urls* is a dictionary mapping class names to http urls
*graph_options*, *node_options*, *edge_options* are
dictionaries containing key/value pairs to pass on as graphviz
properties.
"""
g_options = self.default_graph_options.copy()
g_options.update(graph_options)
n_options = self.default_node_options.copy()
n_options.update(node_options)
e_options = self.default_edge_options.copy()
e_options.update(edge_options)
fd.write('digraph %s {\n' % name)
fd.write(self._format_graph_options(g_options))
for cls in self.all_classes:
if not self.show_builtins and cls in __builtins__.values():
continue
name = self.class_name(cls, parts)
# Write the node
this_node_options = n_options.copy()
url = urls.get(self.class_name(cls))
if url is not None:
this_node_options['URL'] = '"%s"' % url
fd.write(' "%s" [%s];\n' %
(name, self._format_node_options(this_node_options)))
# Write the edges
for base in cls.__bases__:
if not self.show_builtins and base in __builtins__.values():
continue
base_name = self.class_name(base, parts)
fd.write(' "%s" -> "%s" [%s];\n' %
(base_name, name,
self._format_node_options(e_options)))
fd.write('}\n')
def run_dot(self, args, name, parts=0, urls={},
graph_options={}, node_options={}, edge_options={}):
"""
Run graphviz 'dot' over this graph, returning whatever 'dot'
writes to stdout.
*args* will be passed along as commandline arguments.
*name* is the name of the graph
*urls* is a dictionary mapping class names to http urls
Raises DotException for any of the many os and
installation-related errors that may occur.
"""
try:
dot = subprocess.Popen(['dot'] + list(args),
stdin=subprocess.PIPE, stdout=subprocess.PIPE,
close_fds=True)
except OSError:
raise DotException("Could not execute 'dot'. Are you sure you have 'graphviz' installed?")
except ValueError:
raise DotException("'dot' called with invalid arguments")
except:
raise DotException("Unexpected error calling 'dot'")
self.generate_dot(dot.stdin, name, parts, urls, graph_options,
node_options, edge_options)
dot.stdin.close()
result = dot.stdout.read()
returncode = dot.wait()
if returncode != 0:
raise DotException("'dot' returned the errorcode %d" % returncode)
return result
class inheritance_diagram(Body, Element):
"""
A docutils node to use as a placeholder for the inheritance
diagram.
"""
pass
def inheritance_diagram_directive(name, arguments, options, content, lineno,
content_offset, block_text, state,
state_machine):
"""
Run when the inheritance_diagram directive is first encountered.
"""
node = inheritance_diagram()
class_names = arguments
# Create a graph starting with the list of classes
graph = InheritanceGraph(class_names)
# Create xref nodes for each target of the graph's image map and
# add them to the doc tree so that Sphinx can resolve the
# references to real URLs later. These nodes will eventually be
# removed from the doctree after we're done with them.
for name in graph.get_all_class_names():
refnodes, x = xfileref_role(
'class', ':class:`%s`' % name, name, 0, state)
node.extend(refnodes)
# Store the graph object so we can use it to generate the
# dot file later
node['graph'] = graph
# Store the original content for use as a hash
node['parts'] = options.get('parts', 0)
node['content'] = " ".join(class_names)
return [node]
def get_graph_hash(node):
return md5(node['content'] + str(node['parts'])).hexdigest()[-10:]
def html_output_graph(self, node):
"""
Output the graph for HTML. This will insert a PNG with clickable
image map.
"""
graph = node['graph']
parts = node['parts']
graph_hash = get_graph_hash(node)
name = "inheritance%s" % graph_hash
path = '_images'
dest_path = os.path.join(setup.app.builder.outdir, path)
if not os.path.exists(dest_path):
os.makedirs(dest_path)
png_path = os.path.join(dest_path, name + ".png")
path = setup.app.builder.imgpath
# Create a mapping from fully-qualified class names to URLs.
urls = {}
for child in node:
if child.get('refuri') is not None:
urls[child['reftitle']] = child.get('refuri')
elif child.get('refid') is not None:
urls[child['reftitle']] = '#' + child.get('refid')
# These arguments to dot will save a PNG file to disk and write
# an HTML image map to stdout.
image_map = graph.run_dot(['-Tpng', '-o%s' % png_path, '-Tcmapx'],
name, parts, urls)
return ('<img src="%s/%s.png" usemap="#%s" class="inheritance"/>%s' %
(path, name, name, image_map))
def latex_output_graph(self, node):
"""
Output the graph for LaTeX. This will insert a PDF.
"""
graph = node['graph']
parts = node['parts']
graph_hash = get_graph_hash(node)
name = "inheritance%s" % graph_hash
dest_path = os.path.abspath(os.path.join(setup.app.builder.outdir, '_images'))
if not os.path.exists(dest_path):
os.makedirs(dest_path)
pdf_path = os.path.abspath(os.path.join(dest_path, name + ".pdf"))
graph.run_dot(['-Tpdf', '-o%s' % pdf_path],
name, parts, graph_options={'size': '"6.0,6.0"'})
return '\n\\includegraphics{%s}\n\n' % pdf_path
def visit_inheritance_diagram(inner_func):
"""
This is just a wrapper around html/latex_output_graph to make it
easier to handle errors and insert warnings.
"""
def visitor(self, node):
try:
content = inner_func(self, node)
except DotException, e:
# Insert the exception as a warning in the document
warning = self.document.reporter.warning(str(e), line=node.line)
warning.parent = node
node.children = [warning]
else:
source = self.document.attributes['source']
self.body.append(content)
node.children = []
return visitor
def do_nothing(self, node):
pass
def setup(app):
setup.app = app
setup.confdir = app.confdir
app.add_node(
inheritance_diagram,
latex=(visit_inheritance_diagram(latex_output_graph), do_nothing),
html=(visit_inheritance_diagram(html_output_graph), do_nothing))
app.add_directive(
'inheritance-diagram', inheritance_diagram_directive,
False, (1, 100, 0), parts = directives.nonnegative_int)

View file

@ -4,7 +4,6 @@ XXX - See what improvements can be made based on the new (as of Sept 2009)
'pycon' lexer for the python console. At the very least it will give better 'pycon' lexer for the python console. At the very least it will give better
highlighted tracebacks. highlighted tracebacks.
""" """
from __future__ import print_function
#----------------------------------------------------------------------------- #-----------------------------------------------------------------------------
# Needed modules # Needed modules
@ -113,3 +112,4 @@ def setup(app):
#----------------------------------------------------------------------------- #-----------------------------------------------------------------------------
# Register the extension as a valid pygments lexer # Register the extension as a valid pygments lexer
highlighting.lexers['ipython'] = IPythonConsoleLexer() highlighting.lexers['ipython'] = IPythonConsoleLexer()

View file

@ -71,14 +71,17 @@ except ImportError:
from md5 import md5 from md5 import md5
# Third-party # Third-party
import matplotlib try:
import matplotlib
matplotlib.use('Agg')
except ImportError:
print "Couldn't find matplotlib"
import sphinx import sphinx
from docutils.parsers.rst import directives from docutils.parsers.rst import directives
from docutils import nodes from docutils import nodes
from sphinx.util.compat import Directive from sphinx.util.compat import Directive
matplotlib.use('Agg')
# Our own # Our own
from IPython import Config, InteractiveShell from IPython import Config, InteractiveShell
from IPython.core.profiledir import ProfileDir from IPython.core.profiledir import ProfileDir
@ -828,3 +831,5 @@ if __name__=='__main__':
os.mkdir('_static') os.mkdir('_static')
test() test()
print 'All OK? Check figures in _static/' print 'All OK? Check figures in _static/'

View file

@ -1,120 +0,0 @@
from __future__ import print_function
import os
import sys
try:
from hashlib import md5
except ImportError:
from md5 import md5
from docutils import nodes
from docutils.parsers.rst import directives
import warnings
from matplotlib import rcParams
from matplotlib.mathtext import MathTextParser
rcParams['mathtext.fontset'] = 'cm'
mathtext_parser = MathTextParser("Bitmap")
# Define LaTeX math node:
class latex_math(nodes.General, nodes.Element):
pass
def fontset_choice(arg):
return directives.choice(arg, ['cm', 'stix', 'stixsans'])
options_spec = {'fontset': fontset_choice}
def math_role(role, rawtext, text, lineno, inliner,
options={}, content=[]):
i = rawtext.find('`')
latex = rawtext[i+1:-1]
node = latex_math(rawtext)
node['latex'] = latex
node['fontset'] = options.get('fontset', 'cm')
return [node], []
math_role.options = options_spec
def math_directive(name, arguments, options, content, lineno,
content_offset, block_text, state, state_machine):
latex = ''.join(content)
node = latex_math(block_text)
node['latex'] = latex
node['fontset'] = options.get('fontset', 'cm')
return [node]
# This uses mathtext to render the expression
def latex2png(latex, filename, fontset='cm'):
latex = "$%s$" % latex
orig_fontset = rcParams['mathtext.fontset']
rcParams['mathtext.fontset'] = fontset
if os.path.exists(filename):
depth = mathtext_parser.get_depth(latex, dpi=100)
else:
try:
depth = mathtext_parser.to_png(filename, latex, dpi=100)
except:
warnings.warn("Could not render math expression %s" % latex,
Warning)
depth = 0
rcParams['mathtext.fontset'] = orig_fontset
sys.stdout.write("#")
sys.stdout.flush()
return depth
# LaTeX to HTML translation stuff:
def latex2html(node, source):
inline = isinstance(node.parent, nodes.TextElement)
latex = node['latex']
name = 'math-%s' % md5(latex).hexdigest()[-10:]
destdir = os.path.join(setup.app.builder.outdir, '_images', 'mathmpl')
if not os.path.exists(destdir):
os.makedirs(destdir)
dest = os.path.join(destdir, '%s.png' % name)
path = os.path.join(setup.app.builder.imgpath, 'mathmpl')
depth = latex2png(latex, dest, node['fontset'])
if inline:
cls = ''
else:
cls = 'class="center" '
if inline and depth != 0:
style = 'style="position: relative; bottom: -%dpx"' % (depth + 1)
else:
style = ''
return '<img src="%s/%s.png" %s%s/>' % (path, name, cls, style)
def setup(app):
setup.app = app
app.add_node(latex_math)
app.add_role('math', math_role)
# Add visit/depart methods to HTML-Translator:
def visit_latex_math_html(self, node):
source = self.document.attributes['source']
self.body.append(latex2html(node, source))
def depart_latex_math_html(self, node):
pass
# Add visit/depart methods to LaTeX-Translator:
def visit_latex_math_latex(self, node):
inline = isinstance(node.parent, nodes.TextElement)
if inline:
self.body.append('$%s$' % node['latex'])
else:
self.body.extend(['\\begin{equation}',
node['latex'],
'\\end{equation}'])
def depart_latex_math_latex(self, node):
pass
app.add_node(latex_math, html=(visit_latex_math_html,
depart_latex_math_html))
app.add_node(latex_math, latex=(visit_latex_math_latex,
depart_latex_math_latex))
app.add_role('math', math_role)
app.add_directive('math', math_directive,
True, (0, 0, 0), **options_spec)

View file

@ -1,116 +0,0 @@
"""
========
numpydoc
========
Sphinx extension that handles docstrings in the Numpy standard format. [1]
It will:
- Convert Parameters etc. sections to field lists.
- Convert See Also section to a See also entry.
- Renumber references.
- Extract the signature from the docstring, if it can't be determined otherwise.
.. [1] http://projects.scipy.org/scipy/numpy/wiki/CodingStyleGuidelines#docstring-standard
"""
import os, re, pydoc
from docscrape_sphinx import get_doc_object, SphinxDocString
import inspect
def mangle_docstrings(app, what, name, obj, options, lines,
reference_offset=[0]):
if what == 'module':
# Strip top title
title_re = re.compile(r'^\s*[#*=]{4,}\n[a-z0-9 -]+\n[#*=]{4,}\s*',
re.I|re.S)
lines[:] = title_re.sub('', "\n".join(lines)).split("\n")
else:
doc = get_doc_object(obj, what, "\n".join(lines))
lines[:] = str(doc).split("\n")
if app.config.numpydoc_edit_link and hasattr(obj, '__name__') and \
obj.__name__:
if hasattr(obj, '__module__'):
v = dict(full_name="%s.%s" % (obj.__module__, obj.__name__))
else:
v = dict(full_name=obj.__name__)
lines += ['', '.. htmlonly::', '']
lines += [' %s' % x for x in
(app.config.numpydoc_edit_link % v).split("\n")]
# replace reference numbers so that there are no duplicates
references = []
for l in lines:
l = l.strip()
if l.startswith('.. ['):
try:
references.append(int(l[len('.. ['):l.index(']')]))
except ValueError:
print "WARNING: invalid reference in %s docstring" % name
# Start renaming from the biggest number, otherwise we may
# overwrite references.
references.sort()
if references:
for i, line in enumerate(lines):
for r in references:
new_r = reference_offset[0] + r
lines[i] = lines[i].replace('[%d]_' % r,
'[%d]_' % new_r)
lines[i] = lines[i].replace('.. [%d]' % r,
'.. [%d]' % new_r)
reference_offset[0] += len(references)
def mangle_signature(app, what, name, obj, options, sig, retann):
# Do not try to inspect classes that don't define `__init__`
if (inspect.isclass(obj) and
'initializes x; see ' in pydoc.getdoc(obj.__init__)):
return '', ''
if not (callable(obj) or hasattr(obj, '__argspec_is_invalid_')): return
if not hasattr(obj, '__doc__'): return
doc = SphinxDocString(pydoc.getdoc(obj))
if doc['Signature']:
sig = re.sub("^[^(]*", "", doc['Signature'])
return sig, ''
def initialize(app):
try:
app.connect('autodoc-process-signature', mangle_signature)
except:
monkeypatch_sphinx_ext_autodoc()
def setup(app, get_doc_object_=get_doc_object):
global get_doc_object
get_doc_object = get_doc_object_
app.connect('autodoc-process-docstring', mangle_docstrings)
app.connect('builder-inited', initialize)
app.add_config_value('numpydoc_edit_link', None, True)
#------------------------------------------------------------------------------
# Monkeypatch sphinx.ext.autodoc to accept argspecless autodocs (Sphinx < 0.5)
#------------------------------------------------------------------------------
def monkeypatch_sphinx_ext_autodoc():
global _original_format_signature
import sphinx.ext.autodoc
if sphinx.ext.autodoc.format_signature is our_format_signature:
return
print "[numpydoc] Monkeypatching sphinx.ext.autodoc ..."
_original_format_signature = sphinx.ext.autodoc.format_signature
sphinx.ext.autodoc.format_signature = our_format_signature
def our_format_signature(what, obj):
r = mangle_signature(None, what, None, obj, None, None, None)
if r is not None:
return r[0]
else:
return _original_format_signature(what, obj)

View file

@ -1,64 +0,0 @@
#
# A pair of directives for inserting content that will only appear in
# either html or latex.
#
from __future__ import print_function
from docutils.nodes import Body, Element
from docutils.parsers.rst import directives
class only_base(Body, Element):
def dont_traverse(self, *args, **kwargs):
return []
class html_only(only_base):
pass
class latex_only(only_base):
pass
def run(content, node_class, state, content_offset):
text = '\n'.join(content)
node = node_class(text)
state.nested_parse(content, content_offset, node)
return [node]
def html_only_directive(name, arguments, options, content, lineno,
content_offset, block_text, state, state_machine):
return run(content, html_only, state, content_offset)
def latex_only_directive(name, arguments, options, content, lineno,
content_offset, block_text, state, state_machine):
return run(content, latex_only, state, content_offset)
def builder_inited(app):
if app.builder.name == 'html':
latex_only.traverse = only_base.dont_traverse
else:
html_only.traverse = only_base.dont_traverse
def setup(app):
app.add_directive('htmlonly', html_only_directive, True, (0, 0, 0))
app.add_directive('latexonly', latex_only_directive, True, (0, 0, 0))
app.add_node(html_only)
app.add_node(latex_only)
# This will *really* never see the light of day As it turns out,
# this results in "broken" image nodes since they never get
# processed, so best not to do this.
# app.connect('builder-inited', builder_inited)
# Add visit/depart methods to HTML-Translator:
def visit_perform(self, node):
pass
def depart_perform(self, node):
pass
def visit_ignore(self, node):
node.children = []
def depart_ignore(self, node):
node.children = []
app.add_node(html_only, html=(visit_perform, depart_perform))
app.add_node(html_only, latex=(visit_ignore, depart_ignore))
app.add_node(latex_only, latex=(visit_perform, depart_perform))
app.add_node(latex_only, html=(visit_ignore, depart_ignore))

View file

@ -1,819 +0,0 @@
"""
A directive for including a matplotlib plot in a Sphinx document.
By default, in HTML output, `plot` will include a .png file with a
link to a high-res .png and .pdf. In LaTeX output, it will include a
.pdf.
The source code for the plot may be included in one of three ways:
1. **A path to a source file** as the argument to the directive::
.. plot:: path/to/plot.py
When a path to a source file is given, the content of the
directive may optionally contain a caption for the plot::
.. plot:: path/to/plot.py
This is the caption for the plot
Additionally, one my specify the name of a function to call (with
no arguments) immediately after importing the module::
.. plot:: path/to/plot.py plot_function1
2. Included as **inline content** to the directive::
.. plot::
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
img = mpimg.imread('_static/stinkbug.png')
imgplot = plt.imshow(img)
3. Using **doctest** syntax::
.. plot::
A plotting example:
>>> import matplotlib.pyplot as plt
>>> plt.plot([1,2,3], [4,5,6])
Options
-------
The ``plot`` directive supports the following options:
format : {'python', 'doctest'}
Specify the format of the input
include-source : bool
Whether to display the source code. The default can be changed
using the `plot_include_source` variable in conf.py
encoding : str
If this source file is in a non-UTF8 or non-ASCII encoding,
the encoding must be specified using the `:encoding:` option.
The encoding will not be inferred using the ``-*- coding -*-``
metacomment.
context : bool
If provided, the code will be run in the context of all
previous plot directives for which the `:context:` option was
specified. This only applies to inline code plot directives,
not those run from files.
nofigs : bool
If specified, the code block will be run, but no figures will
be inserted. This is usually useful with the ``:context:``
option.
Additionally, this directive supports all of the options of the
`image` directive, except for `target` (since plot will add its own
target). These include `alt`, `height`, `width`, `scale`, `align` and
`class`.
Configuration options
---------------------
The plot directive has the following configuration options:
plot_include_source
Default value for the include-source option
plot_pre_code
Code that should be executed before each plot.
plot_basedir
Base directory, to which ``plot::`` file names are relative
to. (If None or empty, file names are relative to the
directoly where the file containing the directive is.)
plot_formats
File formats to generate. List of tuples or strings::
[(suffix, dpi), suffix, ...]
that determine the file format and the DPI. For entries whose
DPI was omitted, sensible defaults are chosen.
plot_html_show_formats
Whether to show links to the files in HTML.
plot_rcparams
A dictionary containing any non-standard rcParams that should
be applied before each plot.
plot_apply_rcparams
By default, rcParams are applied when `context` option is not used in
a plot directive. This configuration option overrides this behaviour
and applies rcParams before each plot.
plot_working_directory
By default, the working directory will be changed to the directory of
the example, so the code can get at its data files, if any. Also its
path will be added to `sys.path` so it can import any helper modules
sitting beside it. This configuration option can be used to specify
a central directory (also added to `sys.path`) where data files and
helper modules for all code are located.
plot_template
Provide a customized template for preparing resturctured text.
"""
from __future__ import print_function
import sys, os, glob, shutil, imp, warnings, cStringIO, re, textwrap, \
traceback, exceptions
from docutils.parsers.rst import directives
from docutils import nodes
from docutils.parsers.rst.directives.images import Image
align = Image.align
import sphinx
sphinx_version = sphinx.__version__.split(".")
# The split is necessary for sphinx beta versions where the string is
# '6b1'
sphinx_version = tuple([int(re.split('[a-z]', x)[0])
for x in sphinx_version[:2]])
try:
# Sphinx depends on either Jinja or Jinja2
import jinja2
def format_template(template, **kw):
return jinja2.Template(template).render(**kw)
except ImportError:
import jinja
def format_template(template, **kw):
return jinja.from_string(template, **kw)
import matplotlib
import matplotlib.cbook as cbook
matplotlib.use('Agg')
import matplotlib.pyplot as plt
from matplotlib import _pylab_helpers
__version__ = 2
#------------------------------------------------------------------------------
# Relative pathnames
#------------------------------------------------------------------------------
# os.path.relpath is new in Python 2.6
try:
from os.path import relpath
except ImportError:
# Copied from Python 2.7
if 'posix' in sys.builtin_module_names:
def relpath(path, start=os.path.curdir):
"""Return a relative version of a path"""
from os.path import sep, curdir, join, abspath, commonprefix, \
pardir
if not path:
raise ValueError("no path specified")
start_list = abspath(start).split(sep)
path_list = abspath(path).split(sep)
# Work out how much of the filepath is shared by start and path.
i = len(commonprefix([start_list, path_list]))
rel_list = [pardir] * (len(start_list)-i) + path_list[i:]
if not rel_list:
return curdir
return join(*rel_list)
elif 'nt' in sys.builtin_module_names:
def relpath(path, start=os.path.curdir):
"""Return a relative version of a path"""
from os.path import sep, curdir, join, abspath, commonprefix, \
pardir, splitunc
if not path:
raise ValueError("no path specified")
start_list = abspath(start).split(sep)
path_list = abspath(path).split(sep)
if start_list[0].lower() != path_list[0].lower():
unc_path, rest = splitunc(path)
unc_start, rest = splitunc(start)
if bool(unc_path) ^ bool(unc_start):
raise ValueError("Cannot mix UNC and non-UNC paths (%s and %s)"
% (path, start))
else:
raise ValueError("path is on drive %s, start on drive %s"
% (path_list[0], start_list[0]))
# Work out how much of the filepath is shared by start and path.
for i in range(min(len(start_list), len(path_list))):
if start_list[i].lower() != path_list[i].lower():
break
else:
i += 1
rel_list = [pardir] * (len(start_list)-i) + path_list[i:]
if not rel_list:
return curdir
return join(*rel_list)
else:
raise RuntimeError("Unsupported platform (no relpath available!)")
#------------------------------------------------------------------------------
# Registration hook
#------------------------------------------------------------------------------
def plot_directive(name, arguments, options, content, lineno,
content_offset, block_text, state, state_machine):
return run(arguments, content, options, state_machine, state, lineno)
plot_directive.__doc__ = __doc__
def _option_boolean(arg):
if not arg or not arg.strip():
# no argument given, assume used as a flag
return True
elif arg.strip().lower() in ('no', '0', 'false'):
return False
elif arg.strip().lower() in ('yes', '1', 'true'):
return True
else:
raise ValueError('"%s" unknown boolean' % arg)
def _option_format(arg):
return directives.choice(arg, ('python', 'doctest'))
def _option_align(arg):
return directives.choice(arg, ("top", "middle", "bottom", "left", "center",
"right"))
def mark_plot_labels(app, document):
"""
To make plots referenceable, we need to move the reference from
the "htmlonly" (or "latexonly") node to the actual figure node
itself.
"""
for name, explicit in document.nametypes.iteritems():
if not explicit:
continue
labelid = document.nameids[name]
if labelid is None:
continue
node = document.ids[labelid]
if node.tagname in ('html_only', 'latex_only'):
for n in node:
if n.tagname == 'figure':
sectname = name
for c in n:
if c.tagname == 'caption':
sectname = c.astext()
break
node['ids'].remove(labelid)
node['names'].remove(name)
n['ids'].append(labelid)
n['names'].append(name)
document.settings.env.labels[name] = \
document.settings.env.docname, labelid, sectname
break
def setup(app):
setup.app = app
setup.config = app.config
setup.confdir = app.confdir
options = {'alt': directives.unchanged,
'height': directives.length_or_unitless,
'width': directives.length_or_percentage_or_unitless,
'scale': directives.nonnegative_int,
'align': _option_align,
'class': directives.class_option,
'include-source': _option_boolean,
'format': _option_format,
'context': directives.flag,
'nofigs': directives.flag,
'encoding': directives.encoding
}
app.add_directive('plot', plot_directive, True, (0, 2, False), **options)
app.add_config_value('plot_pre_code', None, True)
app.add_config_value('plot_include_source', False, True)
app.add_config_value('plot_formats', ['png', 'hires.png', 'pdf'], True)
app.add_config_value('plot_basedir', None, True)
app.add_config_value('plot_html_show_formats', True, True)
app.add_config_value('plot_rcparams', {}, True)
app.add_config_value('plot_apply_rcparams', False, True)
app.add_config_value('plot_working_directory', None, True)
app.add_config_value('plot_template', None, True)
app.connect('doctree-read', mark_plot_labels)
#------------------------------------------------------------------------------
# Doctest handling
#------------------------------------------------------------------------------
def contains_doctest(text):
try:
# check if it's valid Python as-is
compile(text, '<string>', 'exec')
return False
except SyntaxError:
pass
r = re.compile(r'^\s*>>>', re.M)
m = r.search(text)
return bool(m)
def unescape_doctest(text):
"""
Extract code from a piece of text, which contains either Python code
or doctests.
"""
if not contains_doctest(text):
return text
code = ""
for line in text.split("\n"):
m = re.match(r'^\s*(>>>|\.\.\.) (.*)$', line)
if m:
code += m.group(2) + "\n"
elif line.strip():
code += "# " + line.strip() + "\n"
else:
code += "\n"
return code
def split_code_at_show(text):
"""
Split code at plt.show()
"""
parts = []
is_doctest = contains_doctest(text)
part = []
for line in text.split("\n"):
if (not is_doctest and line.strip() == 'plt.show()') or \
(is_doctest and line.strip() == '>>> plt.show()'):
part.append(line)
parts.append("\n".join(part))
part = []
else:
part.append(line)
if "\n".join(part).strip():
parts.append("\n".join(part))
return parts
#------------------------------------------------------------------------------
# Template
#------------------------------------------------------------------------------
TEMPLATE = """
{{ source_code }}
{{ only_html }}
{% if source_link or (html_show_formats and not multi_image) %}
(
{%- if source_link -%}
`Source code <{{ source_link }}>`__
{%- endif -%}
{%- if html_show_formats and not multi_image -%}
{%- for img in images -%}
{%- for fmt in img.formats -%}
{%- if source_link or not loop.first -%}, {% endif -%}
`{{ fmt }} <{{ dest_dir }}/{{ img.basename }}.{{ fmt }}>`__
{%- endfor -%}
{%- endfor -%}
{%- endif -%}
)
{% endif %}
{% for img in images %}
.. figure:: {{ build_dir }}/{{ img.basename }}.png
{%- for option in options %}
{{ option }}
{% endfor %}
{% if html_show_formats and multi_image -%}
(
{%- for fmt in img.formats -%}
{%- if not loop.first -%}, {% endif -%}
`{{ fmt }} <{{ dest_dir }}/{{ img.basename }}.{{ fmt }}>`__
{%- endfor -%}
)
{%- endif -%}
{{ caption }}
{% endfor %}
{{ only_latex }}
{% for img in images %}
.. image:: {{ build_dir }}/{{ img.basename }}.pdf
{% endfor %}
{{ only_texinfo }}
{% for img in images %}
.. image:: {{ build_dir }}/{{ img.basename }}.png
{%- for option in options %}
{{ option }}
{% endfor %}
{% endfor %}
"""
exception_template = """
.. htmlonly::
[`source code <%(linkdir)s/%(basename)s.py>`__]
Exception occurred rendering plot.
"""
# the context of the plot for all directives specified with the
# :context: option
plot_context = dict()
class ImageFile(object):
def __init__(self, basename, dirname):
self.basename = basename
self.dirname = dirname
self.formats = []
def filename(self, format):
return os.path.join(self.dirname, "%s.%s" % (self.basename, format))
def filenames(self):
return [self.filename(fmt) for fmt in self.formats]
def out_of_date(original, derived):
"""
Returns True if derivative is out-of-date wrt original,
both of which are full file paths.
"""
return (not os.path.exists(derived) or
(os.path.exists(original) and
os.stat(derived).st_mtime < os.stat(original).st_mtime))
class PlotError(RuntimeError):
pass
def run_code(code, code_path, ns=None, function_name=None):
"""
Import a Python module from a path, and run the function given by
name, if function_name is not None.
"""
# Change the working directory to the directory of the example, so
# it can get at its data files, if any. Add its path to sys.path
# so it can import any helper modules sitting beside it.
pwd = os.getcwd()
old_sys_path = list(sys.path)
if setup.config.plot_working_directory is not None:
try:
os.chdir(setup.config.plot_working_directory)
except OSError as err:
raise OSError(str(err) + '\n`plot_working_directory` option in'
'Sphinx configuration file must be a valid '
'directory path')
except TypeError as err:
raise TypeError(str(err) + '\n`plot_working_directory` option in '
'Sphinx configuration file must be a string or '
'None')
sys.path.insert(0, setup.config.plot_working_directory)
elif code_path is not None:
dirname = os.path.abspath(os.path.dirname(code_path))
os.chdir(dirname)
sys.path.insert(0, dirname)
# Redirect stdout
stdout = sys.stdout
sys.stdout = cStringIO.StringIO()
# Reset sys.argv
old_sys_argv = sys.argv
sys.argv = [code_path]
try:
try:
code = unescape_doctest(code)
if ns is None:
ns = {}
if not ns:
if setup.config.plot_pre_code is None:
exec "import numpy as np\nfrom matplotlib import pyplot as plt\n" in ns
else:
exec setup.config.plot_pre_code in ns
if "__main__" in code:
exec "__name__ = '__main__'" in ns
exec code in ns
if function_name is not None:
exec function_name + "()" in ns
except (Exception, SystemExit), err:
raise PlotError(traceback.format_exc())
finally:
os.chdir(pwd)
sys.argv = old_sys_argv
sys.path[:] = old_sys_path
sys.stdout = stdout
return ns
def clear_state(plot_rcparams):
plt.close('all')
matplotlib.rc_file_defaults()
matplotlib.rcParams.update(plot_rcparams)
def render_figures(code, code_path, output_dir, output_base, context,
function_name, config):
"""
Run a pyplot script and save the low and high res PNGs and a PDF
in outdir.
Save the images under *output_dir* with file names derived from
*output_base*
"""
# -- Parse format list
default_dpi = {'png': 80, 'hires.png': 200, 'pdf': 200}
formats = []
plot_formats = config.plot_formats
if isinstance(plot_formats, (str, unicode)):
plot_formats = eval(plot_formats)
for fmt in plot_formats:
if isinstance(fmt, str):
formats.append((fmt, default_dpi.get(fmt, 80)))
elif type(fmt) in (tuple, list) and len(fmt)==2:
formats.append((str(fmt[0]), int(fmt[1])))
else:
raise PlotError('invalid image format "%r" in plot_formats' % fmt)
# -- Try to determine if all images already exist
code_pieces = split_code_at_show(code)
# Look for single-figure output files first
# Look for single-figure output files first
all_exists = True
img = ImageFile(output_base, output_dir)
for format, dpi in formats:
if out_of_date(code_path, img.filename(format)):
all_exists = False
break
img.formats.append(format)
if all_exists:
return [(code, [img])]
# Then look for multi-figure output files
results = []
all_exists = True
for i, code_piece in enumerate(code_pieces):
images = []
for j in xrange(1000):
if len(code_pieces) > 1:
img = ImageFile('%s_%02d_%02d' % (output_base, i, j), output_dir)
else:
img = ImageFile('%s_%02d' % (output_base, j), output_dir)
for format, dpi in formats:
if out_of_date(code_path, img.filename(format)):
all_exists = False
break
img.formats.append(format)
# assume that if we have one, we have them all
if not all_exists:
all_exists = (j > 0)
break
images.append(img)
if not all_exists:
break
results.append((code_piece, images))
if all_exists:
return results
# We didn't find the files, so build them
results = []
if context:
ns = plot_context
else:
ns = {}
for i, code_piece in enumerate(code_pieces):
if not context or config.plot_apply_rcparams:
clear_state(config.plot_rcparams)
run_code(code_piece, code_path, ns, function_name)
images = []
fig_managers = _pylab_helpers.Gcf.get_all_fig_managers()
for j, figman in enumerate(fig_managers):
if len(fig_managers) == 1 and len(code_pieces) == 1:
img = ImageFile(output_base, output_dir)
elif len(code_pieces) == 1:
img = ImageFile("%s_%02d" % (output_base, j), output_dir)
else:
img = ImageFile("%s_%02d_%02d" % (output_base, i, j),
output_dir)
images.append(img)
for format, dpi in formats:
try:
figman.canvas.figure.savefig(img.filename(format), dpi=dpi)
except Exception,err:
raise PlotError(traceback.format_exc())
img.formats.append(format)
results.append((code_piece, images))
if not context or config.plot_apply_rcparams:
clear_state(config.plot_rcparams)
return results
def run(arguments, content, options, state_machine, state, lineno):
# The user may provide a filename *or* Python code content, but not both
if arguments and content:
raise RuntimeError("plot:: directive can't have both args and content")
document = state_machine.document
config = document.settings.env.config
nofigs = options.has_key('nofigs')
options.setdefault('include-source', config.plot_include_source)
context = options.has_key('context')
rst_file = document.attributes['source']
rst_dir = os.path.dirname(rst_file)
if len(arguments):
if not config.plot_basedir:
source_file_name = os.path.join(setup.app.builder.srcdir,
directives.uri(arguments[0]))
else:
source_file_name = os.path.join(setup.confdir, config.plot_basedir,
directives.uri(arguments[0]))
# If there is content, it will be passed as a caption.
caption = '\n'.join(content)
# If the optional function name is provided, use it
if len(arguments) == 2:
function_name = arguments[1]
else:
function_name = None
with open(source_file_name, 'r') as fd:
code = fd.read()
output_base = os.path.basename(source_file_name)
else:
source_file_name = rst_file
code = textwrap.dedent("\n".join(map(str, content)))
counter = document.attributes.get('_plot_counter', 0) + 1
document.attributes['_plot_counter'] = counter
base, ext = os.path.splitext(os.path.basename(source_file_name))
output_base = '%s-%d.py' % (base, counter)
function_name = None
caption = ''
base, source_ext = os.path.splitext(output_base)
if source_ext in ('.py', '.rst', '.txt'):
output_base = base
else:
source_ext = ''
# ensure that LaTeX includegraphics doesn't choke in foo.bar.pdf filenames
output_base = output_base.replace('.', '-')
# is it in doctest format?
is_doctest = contains_doctest(code)
if options.has_key('format'):
if options['format'] == 'python':
is_doctest = False
else:
is_doctest = True
# determine output directory name fragment
source_rel_name = relpath(source_file_name, setup.confdir)
source_rel_dir = os.path.dirname(source_rel_name)
while source_rel_dir.startswith(os.path.sep):
source_rel_dir = source_rel_dir[1:]
# build_dir: where to place output files (temporarily)
build_dir = os.path.join(os.path.dirname(setup.app.doctreedir),
'plot_directive',
source_rel_dir)
# get rid of .. in paths, also changes pathsep
# see note in Python docs for warning about symbolic links on Windows.
# need to compare source and dest paths at end
build_dir = os.path.normpath(build_dir)
if not os.path.exists(build_dir):
os.makedirs(build_dir)
# output_dir: final location in the builder's directory
dest_dir = os.path.abspath(os.path.join(setup.app.builder.outdir,
source_rel_dir))
if not os.path.exists(dest_dir):
os.makedirs(dest_dir) # no problem here for me, but just use built-ins
# how to link to files from the RST file
dest_dir_link = os.path.join(relpath(setup.confdir, rst_dir),
source_rel_dir).replace(os.path.sep, '/')
build_dir_link = relpath(build_dir, rst_dir).replace(os.path.sep, '/')
source_link = dest_dir_link + '/' + output_base + source_ext
# make figures
try:
results = render_figures(code, source_file_name, build_dir, output_base,
context, function_name, config)
errors = []
except PlotError, err:
reporter = state.memo.reporter
sm = reporter.system_message(
2, "Exception occurred in plotting %s\n from %s:\n%s" % (output_base,
source_file_name, err),
line=lineno)
results = [(code, [])]
errors = [sm]
# Properly indent the caption
caption = '\n'.join(' ' + line.strip()
for line in caption.split('\n'))
# generate output restructuredtext
total_lines = []
for j, (code_piece, images) in enumerate(results):
if options['include-source']:
if is_doctest:
lines = ['']
lines += [row.rstrip() for row in code_piece.split('\n')]
else:
lines = ['.. code-block:: python', '']
lines += [' %s' % row.rstrip()
for row in code_piece.split('\n')]
source_code = "\n".join(lines)
else:
source_code = ""
if nofigs:
images = []
opts = [':%s: %s' % (key, val) for key, val in options.items()
if key in ('alt', 'height', 'width', 'scale', 'align', 'class')]
only_html = ".. only:: html"
only_latex = ".. only:: latex"
only_texinfo = ".. only:: texinfo"
if j == 0:
src_link = source_link
else:
src_link = None
result = format_template(
config.plot_template or TEMPLATE,
dest_dir=dest_dir_link,
build_dir=build_dir_link,
source_link=src_link,
multi_image=len(images) > 1,
only_html=only_html,
only_latex=only_latex,
only_texinfo=only_texinfo,
options=opts,
images=images,
source_code=source_code,
html_show_formats=config.plot_html_show_formats,
caption=caption)
total_lines.extend(result.split("\n"))
total_lines.extend("\n")
if total_lines:
state_machine.insert_input(total_lines, source=source_file_name)
# copy image files to builder's output directory, if necessary
if not os.path.exists(dest_dir):
cbook.mkdirs(dest_dir)
for code_piece, images in results:
for img in images:
for fn in img.filenames():
destimg = os.path.join(dest_dir, os.path.basename(fn))
if fn != destimg:
shutil.copyfile(fn, destimg)
# copy script (if necessary)
target_name = os.path.join(dest_dir, output_base + source_ext)
with open(target_name, 'w') as f:
if source_file_name == rst_file:
code_escaped = unescape_doctest(code)
else:
code_escaped = code
f.write(code_escaped)
return errors

View file

@ -1,4 +1,3 @@
************************************* *************************************
Gaussian process regression tutorial Gaussian process regression tutorial
************************************* *************************************
@ -12,7 +11,7 @@ We first import the libraries we will need: ::
import numpy as np import numpy as np
import GPy import GPy
1 dimensional model 1-dimensional model
=================== ===================
For this toy example, we assume we have the following inputs and outputs:: For this toy example, we assume we have the following inputs and outputs::
@ -22,13 +21,11 @@ For this toy example, we assume we have the following inputs and outputs::
Note that the observations Y include some noise. Note that the observations Y include some noise.
The first step is to define the covariance kernel we want to use for the model. We choose here a kernel based on Gaussian kernel (i.e. rbf or square exponential) plus some white noise:: The first step is to define the covariance kernel we want to use for the model. We choose here a kernel based on Gaussian kernel (i.e. rbf or square exponential)::
Gaussian = GPy.kern.rbf(D=1) kernel = GPy.kern.rbf(D=1, variance=1., lengthscale=1.)
noise = GPy.kern.white(D=1)
kernel = Gaussian + noise
The parameter ``D`` stands for the dimension of the input space. Note that many other kernels are implemented such as: The parameter ``D`` stands for the dimension of the input space. The parameters ``variance`` and ``lengthscale`` are optional. Note that many other kernels are implemented such as:
* linear (``GPy.kern.linear``) * linear (``GPy.kern.linear``)
* exponential kernel (``GPy.kern.exponential``) * exponential kernel (``GPy.kern.exponential``)
@ -41,19 +38,19 @@ The inputs required for building the model are the observations and the kernel::
m = GPy.models.GP_regression(X,Y,kernel) m = GPy.models.GP_regression(X,Y,kernel)
The functions ``print`` and ``plot`` give an insight of the model we have just build. The code:: By default, some observation noise is added to the modle. The functions ``print`` and ``plot`` give an insight of the model we have just build. The code::
print m print m
m.plot() m.plot()
gives the following output: :: gives the following output: ::
Marginal log-likelihood: -2.281e+01 Marginal log-likelihood: -4.479e+00
Name | Value | Constraints | Ties | Prior Name | Value | Constraints | Ties | Prior
----------------------------------------------------------------- -----------------------------------------------------------------
rbf_variance | 1.0000 | | | rbf_variance | 1.0000 | | |
rbf_lengthscale | 1.0000 | | | rbf_lengthscale | 1.0000 | | |
white_variance | 1.0000 | | | noise variance | 1.0000 | | |
.. figure:: Figures/tuto_GP_regression_m1.png .. figure:: Figures/tuto_GP_regression_m1.png
:align: center :align: center
@ -75,24 +72,24 @@ but it is also possible to set a range on to constrain one parameter to be fixed
m.unconstrain('') # Required to remove the previous constrains m.unconstrain('') # Required to remove the previous constrains
m.constrain_positive('rbf_variance') m.constrain_positive('rbf_variance')
m.constrain_bounded('lengthscale',1.,10. ) m.constrain_bounded('lengthscale',1.,10. )
m.constrain_fixed('white',0.0025) m.constrain_fixed('noise',0.0025)
Once the constrains have been imposed, the model can be optimized:: Once the constrains have been imposed, the model can be optimized::
m.optimize() m.optimize()
If we want to perform some restarts to try to improve the result of the optimization, we can use the optimize_restart function:: If we want to perform some restarts to try to improve the result of the optimization, we can use the ``optimize_restart`` function::
m.optimize_restarts(Nrestarts = 10) m.optimize_restarts(Nrestarts = 10)
Once again, we can use ``print(m)`` and ``m.plot()`` to look at the resulting model resulting model:: Once again, we can use ``print(m)`` and ``m.plot()`` to look at the resulting model resulting model::
Marginal log-likelihood: 2.001e+01 Marginal log-likelihood: 3.603e+01
Name | Value | Constraints | Ties | Prior Name | Value | Constraints | Ties | Prior
----------------------------------------------------------------- -----------------------------------------------------------------
rbf_variance | 0.8033 | (+ve) | | rbf_variance | 0.8151 | (+ve) | |
rbf_lengthscale | 1.8033 | (1.0, 10.0) | | rbf_lengthscale | 1.8037 | (1.0, 10.0) | |
white_variance | 0.0025 | Fixed | | noise variance | 0.0025 | Fixed | |
.. figure:: Figures/tuto_GP_regression_m2.png .. figure:: Figures/tuto_GP_regression_m2.png
:align: center :align: center
@ -101,7 +98,7 @@ Once again, we can use ``print(m)`` and ``m.plot()`` to look at the resulting mo
GP regression model after optimization of the parameters. GP regression model after optimization of the parameters.
2 dimensional example 2-dimensional example
===================== =====================
Here is a 2 dimensional example:: Here is a 2 dimensional example::
@ -131,15 +128,16 @@ Here is a 2 dimensional example::
m.plot() m.plot()
print(m) print(m)
The flag ``ARD=True`` in the definition of the Matern kernel specifies that we want one lengthscale parameter per dimension (ie the GP is not isotropic). The output of the last 2 lines is:: The flag ``ARD=True`` in the definition of the Matern kernel specifies that we want one lengthscale parameter per dimension (ie the GP is not isotropic). The output of the last two lines is::
Marginal log-likelihood: 2.893e+01 Marginal log-likelihood: 6.682e+01
Name | Value | Constraints | Ties | Prior Name | Value | Constraints | Ties | Prior
------------------------------------------------------------------------- ---------------------------------------------------------------------
Mat52_ARD_variance | 0.4094 | (+ve) | | Mat52_variance | 0.3860 | (+ve) | |
Mat52_ARD_lengthscale_0 | 2.1060 | (+ve) | | Mat52_lengthscale_0 | 2.0578 | (+ve) | |
Mat52_ARD_lengthscale_1 | 2.0546 | (+ve) | | Mat52_lengthscale_1 | 1.8542 | (+ve) | |
white_variance | 0.0012 | (+ve) | | white_variance | 0.0023 | (+ve) | |
noise variance | 0.0000 | (+ve) | |
.. figure:: Figures/tuto_GP_regression_m3.png .. figure:: Figures/tuto_GP_regression_m3.png
:align: center :align: center

View file

@ -0,0 +1,177 @@
****************************
tutorial : A kernel overview
****************************
First we import the libraries we will need ::
import pylab as pb
import numpy as np
import GPy
pb.ion()
For most kernels, the dimension is the only mandatory parameter to define a kernel object. However, it is also possible to specify the values of the parameters. For example, the three following commands are valid for defining a squared exponential kernel (ie rbf or Gaussian) ::
ker1 = GPy.kern.rbf(1) # Equivalent to ker1 = GPy.kern.rbf(D=1, variance=1., lengthscale=1.)
ker2 = GPy.kern.rbf(D=1, variance = 1.5, lengthscale=2.)
ker3 = GPy.kern.rbf(1, .5, .5)
A `plot` and a `print` functions are implemented to represent kernel objects ::
print ker1
ker1.plot()
ker2.plot()
ker3.plot()
.. figure:: Figures/tuto_kern_overview_basicdef.png
:align: center
:height: 350px
Implemented kernels
===================
Many kernels are already implemented in GPy. Here is a summary of most of them:
.. figure:: Figures/tuto_kern_overview_allkern.png
:align: center
:height: 800px
On the other hand, it is possible to use the `sympy` package to build new kernels. This will be the subject of another tutorial.
Operations to combine kernel
============================
In ``GPy``, kernel objects can be combined with the usual ``+`` and ``*`` operators. ::
k1 = GPy.kern.rbf(1,variance=1., lengthscale=2)
k2 = GPy.kern.Matern32(1,variance=1., lengthscale=2)
ker_add = k1 + k2
print ker_add
ker_prod = k1 * k2
print ker_prod
Note that by default, the operator ``+`` adds kernels defined on the same input space whereas ``*`` assumes that the kernels are defined on different input spaces. Here for example ``ker_add.D`` will return ``1`` whereas ``ker_prod.D`` will return ``2``.
In order to add kernels defined on the different input spaces, the required command is::
ker_add_orth = k1.add_orthogonal(k2)
.. figure:: Figures/tuto_kern_overview_add_orth.png
:align: center
:height: 350px
Output of ``ker_add_orth.plot(plot_limits=[[-10,-10],[10,10]])``.
Example : Building an ANOVA kernel
==================================
In two dimensions ANOVA kernels have the following form:
.. math::
k_{ANOVA}(x,y) = \prod_{i=1}^2 (1 + k_i(x_i,y_i)) = 1 + k_1(x_1,y_1) + k_2(x_2,y_2) + k_1(x_1,y_1) \times k_2(x_2,y_2).
Let us assume that we want to define an ANOVA kernel with a Matern 3/2 kernel for :math:`k_i`. As seen previously, we can define this kernel as follows ::
k_cst = GPy.kern.bias(1,variance=1.)
k_mat = GPy.kern.Matern52(1,variance=1., lengthscale=3)
Kanova = (k_cst + k_mat) * (k_cst + k_mat)
print Kanova
Printing the resulting kernel outputs the following ::
Name | Value | Constraints | Ties
---------------------------------------------------------------------------
bias<times>bias_variance | 1.0000 | |
bias<times>Mat52_variance | 1.0000 | |
bias<times>Mat52_Mat52_lengthscale | 3.0000 | | (1)
Mat52<times>bias_variance | 1.0000 | |
Mat52<times>bias_Mat52_lengthscale | 3.0000 | | (0)
Mat52<times>Mat52_variance | 1.0000 | |
Mat52<times>Mat52_Mat52_lengthscale | 3.0000 | | (0)
Mat52<times>Mat52_Mat52_lengthscale | 3.0000 | | (1)
Note the ties between the lengthscales of ``Kanova`` to keep the number of lengthscales equal to 2. On the other hand, there are four variance terms in the new parameterization: one for each term of the right hand part of the above equation. We can illustrate the use of this kernel on a toy example::
# sample inputs and outputs
X = np.random.uniform(-3.,3.,(40,2))
Y = 0.5*X[:,:1] + 0.5*X[:,1:] + 2*np.sin(X[:,:1]) * np.sin(X[:,1:])
# Create GP regression model
m = GPy.models.GP_regression(X,Y,Kanova)
m.plot()
.. figure:: Figures/tuto_kern_overview_mANOVA.png
:align: center
:height: 350px
As :math:`k_{ANOVA}` corresponds to the sum of 4 kernels, the best predictor can be splited in a sum of 4 functions
.. math::
bp(x) & = k(x)^t K^{-1} Y \\
& = (1 + k_1(x_1) + k_2(x_2) + k_1(x_1)k_2(x_2))^t K^{-1} Y \\
& = 1^t K^{-1} Y + k_1(x_1)^t K^{-1} Y + k_2(x_2)^t K^{-1} Y + (k_1(x_1)k_2(x_2))^t K^{-1} Y
The submodels can be represented with the option ``which_function`` of ``plot``: ::
pb.figure(figsize=(20,5))
pb.subplots_adjust(wspace=0.5)
pb.subplot(1,5,1)
m.plot()
pb.subplot(1,5,2)
pb.ylabel("= ",rotation='horizontal',fontsize='30')
pb.subplot(1,5,3)
m.plot(which_functions=[False,True,False,False])
pb.ylabel("cst +",rotation='horizontal',fontsize='30')
pb.subplot(1,5,4)
m.plot(which_functions=[False,False,True,False])
pb.ylabel("+ ",rotation='horizontal',fontsize='30')
pb.subplot(1,5,5)
pb.ylabel("+ ",rotation='horizontal',fontsize='30')
m.plot(which_functions=[False,False,False,True])
.. figure:: Figures/tuto_kern_overview_mANOVAdec.png
:align: center
:height: 200px
.. import pylab as pb
import numpy as np
import GPy
pb.ion()
ker1 = GPy.kern.rbf(D=1) # Equivalent to ker1 = GPy.kern.rbf(D=1, variance=1., lengthscale=1.)
ker2 = GPy.kern.rbf(D=1, variance = .75, lengthscale=3.)
ker3 = GPy.kern.rbf(1, .5, .25)
ker1.plot()
ker2.plot()
ker3.plot()
#pb.savefig("Figures/tuto_kern_overview_basicdef.png")
kernels = [GPy.kern.rbf(1), GPy.kern.exponential(1), GPy.kern.Matern32(1), GPy.kern.Matern52(1), GPy.kern.Brownian(1), GPy.kern.bias(1), GPy.kern.linear(1), GPy.kern.spline(1), GPy.kern.periodic_exponential(1), GPy.kern.periodic_Matern32(1), GPy.kern.periodic_Matern52(1), GPy.kern.white(1)]
kernel_names = ["GPy.kern.rbf", "GPy.kern.exponential", "GPy.kern.Matern32", "GPy.kern.Matern52", "GPy.kern.Brownian", "GPy.kern.bias", "GPy.kern.linear", "GPy.kern.spline", "GPy.kern.periodic_exponential", "GPy.kern.periodic_Matern32", "GPy.kern.periodic_Matern52", "GPy.kern.white"]
pb.figure(figsize=(16,12))
pb.subplots_adjust(wspace=.5, hspace=.5)
for i, kern in enumerate(kernels):
pb.subplot(3,4,i+1)
kern.plot(x=7.5,plot_limits=[0.00001,15.])
pb.title(kernel_names[i]+ '\n')
#pb.axes([.1,.1,.8,.7])
#pb.figtext(.5,.9,'Foo Bar', fontsize=18, ha='center')
#pb.figtext(.5,.85,'Lorem ipsum dolor sit amet, consectetur adipiscing elit',fontsize=10,ha='center')
# actual plot for the noise
i = 11
X = np.linspace(0.,15.,201)
WN = 0*X
WN[100] = 1.
pb.subplot(3,4,i+1)
pb.plot(X,WN,'b')

View file

@ -1,64 +0,0 @@
import numpy as np
import pylab as pb
pb.ion()
import sys
import GPy
pb.close('all')
N = 200
M = 15
resolution=5
X = np.linspace(0,12,N)[:,None]
Z = np.linspace(0,12,M)[:,None] # inducing points (fixed for now)
Y = np.sin(X) + np.random.randn(*X.shape)/np.sqrt(50.)
#k = GPy.kern.rbf(1)
k = GPy.kern.Matern32(1) + GPy.kern.white(1)
models = [GPy.models.sparse_GP_regression(X,Y,Z=Z,kernel=k)
,GPy.models.sparse_GP_regression(X,Y,Z=Z,kernel=k)
,GPy.models.sparse_GP_regression(X,Y,Z=Z,kernel=k)
,GPy.models.sparse_GP_regression(X,Y,Z=Z,kernel=k)]
models[0].scale_factor = 1.
models[1].scale_factor = 10.
models[2].scale_factor = 100.
models[3].scale_factor = 1000.
#GPy.models.sgp_debugB(X,Y,Z=Z,kernel=k),
#GPy.models.sgp_debugC(X,Y,Z=Z,kernel=k)]#,
#GPy.models.sgp_debugE(X,Y,Z=Z,kernel=k)]
[m.constrain_fixed('white',0.1) for m in models]
#xx,yy = np.mgrid[1.5:4:0+resolution*1j,-2:2:0+resolution*1j]
xx,yy = np.mgrid[3:16:0+resolution*1j,-2:1:0+resolution*1j]
lls = []
cgs = []
grads = []
count = 0
for l,v in zip(xx.flatten(),yy.flatten()):
count += 1
print count, 'of', resolution**2
sys.stdout.flush()
[m.set('lengthscale',l) for m in models]
[m.set('_variance',10.**v) for m in models]
lls.append([m.log_likelihood() for m in models])
grads.append([m.log_likelihood_gradients() for m in models])
cgs.append([m.checkgrad(verbose=0,return_ratio=True) for m in models])
lls = np.array(zip(*lls)).reshape(-1,resolution,resolution)
cgs = np.array(zip(*cgs)).reshape(-1,resolution,resolution)
for ll,cg in zip(lls,cgs):
pb.figure()
pb.contourf(xx,yy,ll,100,cmap=pb.cm.gray)
pb.colorbar()
try:
pb.contour(xx,yy,np.exp(ll),colors='k')
except:
pass
pb.scatter(xx.flatten(),yy.flatten(),20,np.log(np.abs(cg.flatten())),cmap=pb.cm.jet,linewidth=0)
pb.colorbar()

View file

@ -3,7 +3,7 @@
import os import os
from numpy.distutils.core import Extension, setup from numpy.distutils.core import Extension, setup
from sphinx.setup_command import BuildDoc #from sphinx.setup_command import BuildDoc
# Version number # Version number
version = '0.1.3' version = '0.1.3'
@ -19,16 +19,19 @@ setup(name = 'GPy',
license = "BSD 3-clause", license = "BSD 3-clause",
keywords = "machine-learning gaussian-processes kernels", keywords = "machine-learning gaussian-processes kernels",
url = "http://ml.sheffield.ac.uk/GPy/", url = "http://ml.sheffield.ac.uk/GPy/",
packages = ['GPy', 'GPy.core', 'GPy.kern', 'GPy.util', 'GPy.models', 'GPy.inference', 'GPy.examples'], packages = ['GPy', 'GPy.core', 'GPy.kern', 'GPy.util', 'GPy.models', 'GPy.inference', 'GPy.examples', 'GPy.likelihoods'],
package_dir={'GPy': 'GPy'}, package_dir={'GPy': 'GPy'},
package_data = {'GPy': ['GPy/examples']}, package_data = {'GPy': ['GPy/examples']},
py_modules = ['GPy.__init__'], py_modules = ['GPy.__init__'],
long_description=read('README.md'), long_description=read('README.md'),
#ext_modules = [Extension(name = 'GPy.kern.lfmUpsilonf2py', #ext_modules = [Extension(name = 'GPy.kern.lfmUpsilonf2py',
# sources = ['GPy/kern/src/lfmUpsilonf2py.f90'])], # sources = ['GPy/kern/src/lfmUpsilonf2py.f90'])],
install_requires=['mock', 'sympy', 'numpy>=1.6', 'scipy>=0.9','matplotlib>=1.1'], install_requires=['sympy', 'numpy>=1.6', 'scipy>=0.9','matplotlib>=1.1'],
setup_requires=['sphinx'], extras_require = {
cmdclass = {'build_sphinx': BuildDoc}, 'docs':['Sphinx', 'ipython'],
},
#setup_requires=['sphinx'],
#cmdclass = {'build_sphinx': BuildDoc},
classifiers=[ classifiers=[
"Development Status :: 1 - Alpha", "Development Status :: 1 - Alpha",
"Topic :: Machine Learning", "Topic :: Machine Learning",