merged with master

This commit is contained in:
Nicolo Fusi 2013-02-15 11:56:37 +00:00
commit 2abba8cf14
59 changed files with 2845 additions and 1608 deletions

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@ -16,8 +16,13 @@ k = GPy.kern.rbf(Q) + GPy.kern.white(Q, 0.00001)
K = k.K(X)
Y = np.random.multivariate_normal(np.zeros(N),K,D).T
<<<<<<< HEAD
k = GPy.kern.rbf(Q) + GPy.kern.rbf(Q) + GPy.kern.white(Q)
# k = GPy.kern.linear(Q, ARD = True) + GPy.kern.white(Q, 0.00001)
=======
# k = GPy.kern.rbf(Q) + GPy.kern.bias(Q) + GPy.kern.white(Q, 0.00001)
k = GPy.kern.rbf(Q, ARD = False) + GPy.kern.white(Q, 0.00001)
>>>>>>> master
m = GPy.models.Bayesian_GPLVM(Y, Q, kernel = k, M=M)
m.constrain_positive('(rbf|bias|noise|white|S)')
# 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 numpy as np
import GPy
default_seed=10000
######################################
## 2 dimensional example
def crescent_data(model_type='Full', inducing=10, seed=default_seed):
def crescent_data(model_type='Full', inducing=10, seed=default_seed): #FIXME
"""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'].
@ -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').
:type inducing: int
"""
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':
m = GPy.models.GP_EP(data['X'],likelihood)
m = GPy.models.GP(data['X'],likelihood,kernel)
else:
# create sparse GP EP model
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)
# optimize
m.em()
m.optimize()
print(m)
# plot
@ -42,54 +49,67 @@ def crescent_data(model_type='Full', inducing=10, seed=default_seed):
return m
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()
likelihood = GPy.inference.likelihoods.probit(data['Y'][:, 0:1])
# Kernel object
kernel = GPy.kern.rbf(12)
# create simple GP model
m = GPy.models.GP_EP(data['X'],likelihood)
# Likelihood object
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.tie_param('lengthscale')
m.approximate_likelihood()
m.update_likelihood_approximation()
# optimize
# Optimize
m.optimize()
# plot
#m.plot()
print(m)
return m
def toy_linear_1d_classification(model_type='Full', inducing=4, seed=default_seed):
"""Simple 1D classification example.
:param model_type: type of model to fit ['Full', 'FITC', 'DTC'].
def toy_linear_1d_classification(seed=default_seed):
"""
Simple 1D classification example
:param seed : seed value for data generation (default is 4).
: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)
likelihood = GPy.inference.likelihoods.probit(data['Y'][:, 0:1])
assert model_type in ('Full','DTC','FITC')
Y = data['Y'][:, 0:1]
Y[Y == -1] = 0
# create simple GP model
if model_type=='Full':
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)
# Kernel object
kernel = GPy.kern.rbf(1)
m.constrain_positive('var')
m.constrain_positive('len')
m.tie_param('lengthscale')
m.approximate_likelihood()
# Likelihood object
distribution = GPy.likelihoods.likelihood_functions.probit()
likelihood = GPy.likelihoods.EP(Y,distribution)
# Optimize and plot
m.em(plot_all=False) # EM algorithm
# Model definition
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()
print(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()
"""