manual merge in plot_latent

This commit is contained in:
James Hensman 2013-04-12 22:44:11 +01:00
commit 1d094229df
11 changed files with 380 additions and 84 deletions

View file

@ -3,29 +3,30 @@
import numpy as np
import pylab as pb
from matplotlib import pyplot as plt
from matplotlib import pyplot as plt, pyplot
import GPy
from GPy.models.mrd import MRD
default_seed = np.random.seed(123344)
def BGPLVM(seed = default_seed):
def BGPLVM(seed=default_seed):
N = 10
M = 3
Q = 2
D = 4
#generate GPLVM-like data
# generate GPLVM-like data
X = np.random.rand(N, Q)
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
Y = np.random.multivariate_normal(np.zeros(N), K, D).T
k = GPy.kern.linear(Q, ARD = True) + GPy.kern.white(Q)
k = GPy.kern.linear(Q, ARD=True) + GPy.kern.white(Q)
# k = GPy.kern.rbf(Q) + GPy.kern.rbf(Q) + GPy.kern.white(Q)
# 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)
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_fixed('S', 1)
@ -38,44 +39,53 @@ def BGPLVM(seed = default_seed):
# pb.title('After optimisation')
m.ensure_default_constraints()
m.randomize()
m.checkgrad(verbose = 1)
m.checkgrad(verbose=1)
return m
<<<<<<< HEAD
def GPLVM_oil_100(optimize=True):
data = GPy.util.datasets.oil_100()
# create simple GP model
kernel = GPy.kern.rbf(6, ARD = True) + GPy.kern.bias(6)
m = GPy.models.GPLVM(data['X'], 6, kernel=kernel)
=======
def GPLVM_oil_100(optimize=True, M=15):
data = GPy.util.datasets.oil_100()
# create simple GP model
kernel = GPy.kern.rbf(6, ARD=True) + GPy.kern.bias(6)
m = GPy.models.GPLVM(data['X'], 6, kernel=kernel, M=M)
>>>>>>> f6b98160a7c0ace6ca5f795aeb878d30b8aaf6a4
m.data_labels = data['Y'].argmax(axis=1)
# optimize
m.ensure_default_constraints()
if optimize:
m.optimize('scg',messages=1)
m.optimize('scg', messages=1)
# plot
print(m)
m.plot_latent(labels=m.data_labels)
return m
def BGPLVM_oil(optimize=True,N=100,Q=10,M=15,max_f_eval=300):
def BGPLVM_oil(optimize=True, N=100, Q=10, M=15, max_f_eval=300):
data = GPy.util.datasets.oil()
# create simple GP model
kernel = GPy.kern.rbf(Q, ARD = True) + GPy.kern.bias(Q) + GPy.kern.white(Q,0.001)
m = GPy.models.Bayesian_GPLVM(data['X'][:N], Q, kernel = kernel,M=M)
kernel = GPy.kern.rbf(Q, ARD=True) + GPy.kern.bias(Q) + GPy.kern.white(Q, 0.001)
m = GPy.models.Bayesian_GPLVM(data['X'][:N], Q, kernel=kernel, M=M)
m.data_labels = data['Y'][:N].argmax(axis=1)
# optimize
if optimize:
m.constrain_fixed('noise',0.05)
m.constrain_fixed('noise', 0.05)
m.ensure_default_constraints()
m.optimize('scg',messages=1,max_f_eval=max(80,max_f_eval))
m.optimize('scg', messages=1, max_f_eval=max(80, max_f_eval))
m.unconstrain('noise')
m.constrain_positive('noise')
m.optimize('scg',messages=1,max_f_eval=max(0,max_f_eval-80))
m.optimize('scg', messages=1, max_f_eval=max(0, max_f_eval - 80))
else:
m.ensure_default_constraints()
@ -83,7 +93,7 @@ def BGPLVM_oil(optimize=True,N=100,Q=10,M=15,max_f_eval=300):
print(m)
m.plot_latent(labels=m.data_labels)
pb.figure()
pb.bar(np.arange(m.kern.D),1./m.input_sensitivity())
pb.bar(np.arange(m.kern.D), 1. / m.input_sensitivity())
return m
def oil_100():
@ -96,7 +106,52 @@ def oil_100():
# plot
print(m)
#m.plot_latent(labels=data['Y'].argmax(axis=1))
# m.plot_latent(labels=data['Y'].argmax(axis=1))
return m
def mrd_simulation():
# num = 2
ard1 = np.array([1., 1, 0, 0], dtype=float)
ard2 = np.array([0., 1, 1, 0], dtype=float)
ard1[ard1 == 0] = 1E-10
ard2[ard2 == 0] = 1E-10
# ard1i = 1. / ard1
# ard2i = 1. / ard2
# k = GPy.kern.rbf(Q, ARD=True, lengthscale=ard1i) + GPy.kern.bias(Q, 0) + GPy.kern.white(Q, 0.0001)
# Y1 = np.random.multivariate_normal(np.zeros(N), k.K(X), D1).T
# Y1 -= Y1.mean(0)
#
# k = GPy.kern.rbf(Q, ARD=True, lengthscale=ard2i) + GPy.kern.bias(Q, 0) + GPy.kern.white(Q, 0.0001)
# Y2 = np.random.multivariate_normal(np.zeros(N), k.K(X), D2).T
# Y2 -= Y2.mean(0)
# make_params = lambda ard: np.hstack([[1], ard, [1, .3]])
D1, D2, N, M, Q = 50, 100, 150, 15, 4
x = np.linspace(0, 2 * np.pi, N)[:, None]
s1 = np.vectorize(lambda x: np.sin(x))
s2 = np.vectorize(lambda x: np.cos(x))
sS = np.vectorize(lambda x: np.sin(2 * x))
S1 = np.hstack([s1(x), sS(x)])
S2 = np.hstack([s2(x), sS(x)])
Y1 = S1.dot(np.random.randn(S1.shape[1], D1))
Y2 = S2.dot(np.random.randn(S2.shape[1], D2))
k = GPy.kern.rbf(Q, ARD=True) + GPy.kern.bias(Q) + GPy.kern.white(Q)
m = MRD(Y1, Y2, Q=Q, M=M, kernel=k, init="PCA", _debug=False)
m.ensure_default_constraints()
# fig = pyplot.figure("expected", figsize=(8, 3))
# ax = fig.add_subplot(121)
# ax.bar(np.arange(ard1.size) + .1, ard1)
# ax = fig.add_subplot(122)
# ax.bar(np.arange(ard2.size) + .1, ard2)
return m
def brendan_faces():
@ -109,7 +164,7 @@ def brendan_faces():
m.optimize(messages=1, max_f_eval=10000)
ax = m.plot_latent()
y = m.likelihood.Y[0,:]
y = m.likelihood.Y[0, :]
data_show = GPy.util.visualize.image_show(y[None, :], dimensions=(20, 28), transpose=True, invert=False, scale=False)
lvm_visualizer = GPy.util.visualize.lvm(m, data_show, ax)
raw_input('Press enter to finish')
@ -126,10 +181,39 @@ def stick():
m.optimize(messages=1, max_f_eval=10000)
ax = m.plot_latent()
y = m.likelihood.Y[0,:]
y = m.likelihood.Y[0, :]
data_show = GPy.util.visualize.stick_show(y[None, :], connect=data['connect'])
lvm_visualizer = GPy.util.visualize.lvm(m, data_show, ax)
raw_input('Press enter to finish')
plt.close('all')
return m
# def BGPLVM_oil():
# data = GPy.util.datasets.oil()
# Y, X = data['Y'], data['X']
# X -= X.mean(axis=0)
# X /= X.std(axis=0)
#
# Q = 10
# M = 30
#
# kernel = GPy.kern.rbf(Q, ARD=True) + GPy.kern.bias(Q) + GPy.kern.white(Q)
# m = GPy.models.Bayesian_GPLVM(X, Q, kernel=kernel, M=M)
# # m.scale_factor = 100.0
# m.constrain_positive('(white|noise|bias|X_variance|rbf_variance|rbf_length)')
# from sklearn import cluster
# km = cluster.KMeans(M, verbose=10)
# Z = km.fit(m.X).cluster_centers_
# # Z = GPy.util.misc.kmm_init(m.X, M)
# m.set('iip', Z)
# m.set('bias', 1e-4)
# # optimize
# # m.ensure_default_constraints()
#
# import pdb; pdb.set_trace()
# m.optimize('tnc', messages=1)
# print m
# m.plot_latent(labels=data['Y'].argmax(axis=1))
# return m

View file

@ -104,7 +104,8 @@ def SCG(f, gradf, x, optargs=(), maxiters=500, max_f_eval=500, display=True, xto
iteration += 1
if display:
print 'Iteration:', iteration, ' Objective:', fnow, ' Scale:', beta, '\r',
print 'Iteration: {0:<5g} Objective:{1:< 12g} Scale:{2:< 12g}\r'.format(iteration, fnow, beta),
# print 'Iteration:', iteration, ' Objective:', fnow, ' Scale:', beta, '\r',
sys.stdout.flush()
if success:

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@ -75,7 +75,10 @@ class opt_SGD(Optimizer):
return (np.isnan(data).sum(axis=1) == 0)
def check_for_missing(self, data):
return np.isnan(data).sum() > 0
if sp.sparse.issparse(self.model.likelihood.Y):
return True
else:
return np.isnan(data).sum() > 0
def subset_parameter_vector(self, x, samples, param_shapes):
subset = np.array([], dtype = int)
@ -149,10 +152,10 @@ class opt_SGD(Optimizer):
else:
raise NotImplementedError
def step_with_missing_data(self, f_fp, X, step, shapes, sparse_matrix):
def step_with_missing_data(self, f_fp, X, step, shapes):
N, Q = X.shape
if not sparse_matrix:
if not sp.sparse.issparse(self.model.likelihood.Y):
Y = self.model.likelihood.Y
samples = self.non_null_samples(self.model.likelihood.Y)
self.model.N = samples.sum()
@ -165,7 +168,6 @@ class opt_SGD(Optimizer):
if self.model.N == 0 or Y.std() == 0.0:
return 0, step, self.model.N
# FIXME: get rid of self.center, everything should be centered by default
self.model.likelihood._mean = Y.mean()
self.model.likelihood._std = Y.std()
self.model.likelihood.set_data(Y)
@ -173,10 +175,6 @@ class opt_SGD(Optimizer):
j = self.subset_parameter_vector(self.x_opt, samples, shapes)
self.model.X = X[samples]
# if self.center:
# self.model.likelihood.Y -= self.model.likelihood.Y.mean()
# self.model.likelihood.Y /= self.model.likelihood.Y.std()
model_name = self.model.__class__.__name__
if model_name == 'Bayesian_GPLVM':
@ -185,33 +183,31 @@ class opt_SGD(Optimizer):
b, p = self.shift_constraints(j)
f, fp = f_fp(self.x_opt[j])
# momentum_term = self.momentum * step[j]
# step[j] = self.learning_rate[j] * fp
# self.x_opt[j] -= step[j] + momentum_term
step[j] = self.momentum * step[j] + self.learning_rate[j] * fp
self.x_opt[j] -= step[j]
self.restore_constraints(b, p)
# restore likelihood _mean and _std, otherwise when we call set_data(y) on
# the next feature, it will get normalized with the mean and std of this one.
self.model.likelihood._mean = 0
self.model.likelihood._std = 1
return f, step, self.model.N
def opt(self, f_fp=None, f=None, fp=None):
self.x_opt = self.model._get_params_transformed()
X, Y = self.model.X.copy(), self.model.likelihood.Y.copy()
N, Q = self.model.X.shape
D = self.model.likelihood.Y.shape[1]
self.trace = []
sparse_matrix = sp.sparse.issparse(self.model.likelihood.Y)
missing_data = True
if not sparse_matrix:
missing_data = self.check_for_missing(self.model.likelihood.Y)
self.model.likelihood.YYT = None
self.model.likelihood.trYYT = None
self.model.likelihood._mean = 0.0
self.model.likelihood._std = 1.0
N, Q = self.model.X.shape
D = self.model.likelihood.Y.shape[1]
num_params = self.model._get_params()
self.trace = []
missing_data = self.check_for_missing(self.model.likelihood.Y)
step = np.zeros_like(num_params)
for it in range(self.iterations):
@ -224,34 +220,26 @@ class opt_SGD(Optimizer):
b = len(features)/self.batch_size
features = [features[i::b] for i in range(b)]
NLL = []
count = 0
last_printed_count = -1
for j in features:
count += 1
for count, j in enumerate(features):
self.model.D = len(j)
self.model.likelihood.D = len(j)
self.model.likelihood.set_data(Y[:, j])
if missing_data or sparse_matrix:
if missing_data:
shapes = self.get_param_shapes(N, Q)
f, step, Nj = self.step_with_missing_data(f_fp, X, step, shapes, sparse_matrix)
f, step, Nj = self.step_with_missing_data(f_fp, X, step, shapes)
else:
Nj = N
f, fp = f_fp(self.x_opt)
# momentum_term = self.momentum * step # compute momentum using update(t-1)
# step = self.learning_rate * fp # compute update(t)
# self.x_opt -= step + momentum_term
step = self.momentum * step + self.learning_rate * fp
self.x_opt -= step
if self.messages == 2:
noise = self.model.likelihood._variance
status = "evaluating {feature: 5d}/{tot: 5d} \t f: {f: 2.3f} \t non-missing: {nm: 4d}\t noise: {noise: 2.4f}\r".format(feature = count, tot = len(features), f = f, nm = Nj, noise = noise)
sys.stdout.write(status)
sys.stdout.flush()
last_printed_count = count
self.param_traces['noise'].append(noise)
NLL.append(f)
@ -269,7 +257,6 @@ class opt_SGD(Optimizer):
self.model.likelihood.D = D
self.model.likelihood.Y = Y
# self.model.Youter = np.dot(Y, Y.T)
self.trace.append(self.f_opt)
if self.iteration_file is not None:
f = open(self.iteration_file + "iteration%d.pickle" % it, 'w')
@ -282,7 +269,3 @@ class opt_SGD(Optimizer):
status = "SGD Iteration: {0: 3d}/{1: 3d} f: {2: 2.3f}\n".format(it+1, self.iterations, self.f_opt)
sys.stdout.write(status)
sys.stdout.flush()

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@ -52,7 +52,7 @@ class kern(parameterised):
parameterised.__init__(self)
def plot_ARD(self):
def plot_ARD(self, ax=pb.gca()):
"""
If an ARD kernel is present, it bar-plots the ARD parameters
@ -60,17 +60,17 @@ class kern(parameterised):
"""
for p in self.parts:
if hasattr(p, 'ARD') and p.ARD:
pb.figure()
pb.title('ARD parameters, %s kernel' % p.name)
ax.set_title('ARD parameters, %s kernel' % p.name)
if p.name == 'linear':
ard_params = p.variances
else:
ard_params = 1./p.lengthscale
pb.bar(np.arange(len(ard_params))-0.4, ard_params)
ax.bar(np.arange(len(ard_params)) - 0.4, ard_params)
ax.set_xticks(np.arange(len(ard_params)),
["${}$".format(i + 1) for i in range(len(ard_params))])
return ax
def _transform_gradients(self,g):
x = self._get_params()

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@ -227,9 +227,8 @@ class rbf(kernpart):
def weave_psi2(self,mu,Zhat):
weave_options = {'headers' : ['<omp.h>'],
'extra_compile_args': ['-fopenmp -march=native'],
'extra_link_args' : ['-lgomp'],
'compiler' : 'gcc'}
'extra_compile_args': ['-fopenmp -O3'], #-march=native'],
'extra_link_args' : ['-lgomp']}
N,Q = mu.shape
M = Zhat.shape[0]

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@ -22,7 +22,7 @@ class Bayesian_GPLVM(sparse_GP, GPLVM):
:type init: 'PCA'|'random'
"""
def __init__(self, Y, Q, X = None, X_variance = None, init='PCA', M=10, Z=None, kernel=None, **kwargs):
def __init__(self, Y, Q, X=None, X_variance=None, init='PCA', M=10, Z=None, kernel=None, **kwargs):
if X == None:
X = self.initialise_latent(init, Q, Y)
@ -31,7 +31,7 @@ class Bayesian_GPLVM(sparse_GP, GPLVM):
if Z is None:
Z = np.random.permutation(X.copy())[:M]
assert Z.shape[1]==X.shape[1]
assert Z.shape[1] == X.shape[1]
if kernel is None:
kernel = kern.rbf(Q) + kern.white(Q)
@ -40,8 +40,8 @@ class Bayesian_GPLVM(sparse_GP, GPLVM):
sparse_GP.__init__(self, X, Gaussian(Y), kernel, Z=Z, X_variance=X_variance, **kwargs)
def _get_param_names(self):
X_names = sum([['X_%i_%i'%(n,q) for q in range(self.Q)] for n in range(self.N)],[])
S_names = sum([['X_variance_%i_%i'%(n,q) for q in range(self.Q)] for n in range(self.N)],[])
X_names = sum([['X_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], [])
S_names = sum([['X_variance_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], [])
return (X_names + S_names + sparse_GP._get_param_names(self))
def _get_params(self):
@ -56,35 +56,43 @@ class Bayesian_GPLVM(sparse_GP, GPLVM):
"""
return np.hstack((self.X.flatten(), self.X_variance.flatten(), sparse_GP._get_params(self)))
def _set_params(self,x):
def _set_params(self, x):
N, Q = self.N, self.Q
self.X = x[:self.X.size].reshape(N,Q).copy()
self.X_variance = x[(N*Q):(2*N*Q)].reshape(N,Q).copy()
sparse_GP._set_params(self, x[(2*N*Q):])
self.X = x[:self.X.size].reshape(N, Q).copy()
self.X_variance = x[(N * Q):(2 * N * Q)].reshape(N, Q).copy()
sparse_GP._set_params(self, x[(2 * N * Q):])
def dKL_dmuS(self):
dKL_dS = (1. - (1. / self.X_variance)) * 0.5
dKL_dmu = self.X
return dKL_dmu, dKL_dS
def dL_dmuS(self):
dL_dmu_psi0, dL_dS_psi0 = self.kern.dpsi1_dmuS(self.dL_dpsi1,self.Z,self.X,self.X_variance)
dL_dmu_psi1, dL_dS_psi1 = self.kern.dpsi0_dmuS(self.dL_dpsi0,self.Z,self.X,self.X_variance)
dL_dmu_psi2, dL_dS_psi2 = self.kern.dpsi2_dmuS(self.dL_dpsi2,self.Z,self.X,self.X_variance)
dL_dmu_psi0, dL_dS_psi0 = self.kern.dpsi1_dmuS(self.dL_dpsi1, self.Z, self.X, self.X_variance)
dL_dmu_psi1, dL_dS_psi1 = self.kern.dpsi0_dmuS(self.dL_dpsi0, self.Z, self.X, self.X_variance)
dL_dmu_psi2, dL_dS_psi2 = self.kern.dpsi2_dmuS(self.dL_dpsi2, self.Z, self.X, self.X_variance)
dL_dmu = dL_dmu_psi0 + dL_dmu_psi1 + dL_dmu_psi2
dL_dS = dL_dS_psi0 + dL_dS_psi1 + dL_dS_psi2
dKL_dS = (1. - (1./self.X_variance))*0.5
dKL_dmu = self.X
return np.hstack(((dL_dmu - dKL_dmu).flatten(), (dL_dS - dKL_dS).flatten()))
return dL_dmu, dL_dS
def KL_divergence(self):
var_mean = np.square(self.X).sum()
var_S = np.sum(self.X_variance - np.log(self.X_variance))
return 0.5*(var_mean + var_S) - 0.5*self.Q*self.N
return 0.5 * (var_mean + var_S) - 0.5 * self.Q * self.N
def log_likelihood(self):
return sparse_GP.log_likelihood(self) - self.KL_divergence()
def _log_likelihood_gradients(self):
return np.hstack((self.dL_dmuS().flatten(), sparse_GP._log_likelihood_gradients(self)))
dKL_dmu, dKL_dS = self.dKL_dmuS()
dL_dmu, dL_dS = self.dL_dmuS()
# TODO: find way to make faster
dbound_dmuS = np.hstack(((dL_dmu - dKL_dmu).flatten(), (dL_dS - dKL_dS).flatten()))
return np.hstack((dbound_dmuS.flatten(), sparse_GP._log_likelihood_gradients(self)))
def plot_latent(self, which_indices=None,*args, **kwargs):
def plot_latent(self, which_indices=None, *args, **kwargs):
if which_indices is None:
try:
@ -93,6 +101,6 @@ class Bayesian_GPLVM(sparse_GP, GPLVM):
raise ValueError, "cannot Atomatically determine which dimensions to plot, please pass 'which_indices'"
else:
input_1, input_2 = which_indices
ax = GPLVM.plot_latent(self, which_indices=[input_1, input_2],*args, **kwargs)
ax = GPLVM.plot_latent(self, which_indices=[input_1, input_2], *args, **kwargs)
ax.plot(self.Z[:, input_1], self.Z[:, input_2], '^w')
return ax

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@ -60,7 +60,7 @@ class GPLVM(GP):
mu, var, upper, lower = self.predict(Xnew)
pb.plot(mu[:,0], mu[:,1],'k',linewidth=1.5)
def plot_latent(self,labels=None, which_indices=None, resolution=50,ax=pb.gca()):
def plot_latent(self, labels=None, which_indices=None, resolution=50, ax=pb.gca()):
"""
:param labels: a np.array of size self.N containing labels for the points (can be number, strings, etc)
:param resolution: the resolution of the grid on which to evaluate the predictive variance
@ -90,7 +90,7 @@ class GPLVM(GP):
Xtest_full[:, :2] = Xtest
mu, var, low, up = self.predict(Xtest_full)
var = var[:, :1]
ax.imshow(var.reshape(resolution,resolution).T[::-1,:],
ax.imshow(var.reshape(resolution, resolution).T[::-1, :],
extent=[xmin[0], xmax[0], xmin[1], xmax[1]], cmap=pb.cm.binary,interpolation='bilinear')
for i,ul in enumerate(np.unique(labels)):

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@ -11,4 +11,7 @@ from warped_GP import warpedGP
from sparse_GPLVM import sparse_GPLVM
from uncollapsed_sparse_GP import uncollapsed_sparse_GP
from Bayesian_GPLVM import Bayesian_GPLVM
import mrd
MRD = mrd.MRD
del mrd
from generalized_FITC import generalized_FITC

180
GPy/models/mrd.py Normal file
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@ -0,0 +1,180 @@
'''
Created on 10 Apr 2013
@author: Max Zwiessele
'''
from GPy.core import model
from GPy.models.Bayesian_GPLVM import Bayesian_GPLVM
import numpy
from GPy.models.sparse_GP import sparse_GP
import itertools
from matplotlib import pyplot
import pylab
class MRD(model):
"""
Do MRD on given Datasets in Ylist.
All Ys in Ylist are in [N x Dn], where Dn can be different per Yn,
N must be shared across datasets though.
:param Ylist...: observed datasets
:type Ylist: [np.ndarray]
:param names: names for different gplvm models
:type names: [str]
:param Q: latent dimensionality
:type Q: int
:param init: initialisation method for the latent space
:type init: 'PCA'|'random'
:param X:
Initial latent space
:param X_variance:
Initial latent space variance
:param init: [PCA|random]
initialization method to use
:param M:
number of inducing inputs to use
:param Z:
initial inducing inputs
:param kernel:
kernel to use
"""
def __init__(self, *Ylist, **kwargs):
self._debug = False
if kwargs.has_key("_debug"):
self._debug = kwargs['_debug']
del kwargs['_debug']
if kwargs.has_key("names"):
self.names = kwargs['names']
del kwargs['names']
else:
self.names = ["{}".format(i + 1) for i in range(len(Ylist))]
if kwargs.has_key('kernel'):
kernel = kwargs['kernel']
k = lambda: kernel.copy()
del kwargs['kernel']
else:
k = lambda: None
self.bgplvms = [Bayesian_GPLVM(Y, kernel=k(), **kwargs) for Y in Ylist]
self.gref = self.bgplvms[0]
nparams = numpy.array([0] + [sparse_GP._get_params(g).size - g.Z.size for g in self.bgplvms])
self.nparams = nparams.cumsum()
self.Q = self.gref.Q
self.N = self.gref.N
self.NQ = self.N * self.Q
self.M = self.gref.M
self.MQ = self.M * self.Q
model.__init__(self) # @UndefinedVariable
def _get_param_names(self):
# X_names = sum([['X_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], [])
# S_names = sum([['X_variance_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], [])
n1 = self.gref._get_param_names()
n1var = n1[:self.NQ * 2 + self.MQ]
map_names = lambda ns, name: map(lambda x: "{1}_{0}".format(*x),
itertools.izip(ns,
itertools.repeat(name)))
return list(itertools.chain(n1var, *(map_names(\
sparse_GP._get_param_names(g)[self.MQ:], n) \
for g, n in zip(self.bgplvms, self.names))))
def _get_params(self):
"""
return parameter list containing private and shared parameters as follows:
=================================================================
| mu | S | Z || theta1 | theta2 | .. | thetaN |
=================================================================
"""
X = self.gref.X.flatten()
X_var = self.gref.X_variance.flatten()
Z = self.gref.Z.flatten()
thetas = [sparse_GP._get_params(g)[g.Z.size:] for g in self.bgplvms]
params = numpy.hstack([X, X_var, Z, numpy.hstack(thetas)])
return params
def _set_var_params(self, g, X, X_var, Z):
g.X = X
g.X_variance = X_var
g.Z = Z
def _set_kern_params(self, g, p):
g.kern._set_params(p[:g.kern.Nparam])
g.likelihood._set_params(p[g.kern.Nparam:])
def _set_params(self, x):
start = 0; end = self.NQ
X = x[start:end].reshape(self.N, self.Q).copy()
start = end; end += start
X_var = x[start:end].reshape(self.N, self.Q).copy()
start = end; end += self.MQ
Z = x[start:end].reshape(self.M, self.Q).copy()
thetas = x[end:]
# set params for all others:
for g, s, e in itertools.izip(self.bgplvms, self.nparams, self.nparams[1:]):
self._set_var_params(g, X, X_var, Z)
self._set_kern_params(g, thetas[s:e].copy())
g._compute_kernel_matrices()
g._computations()
def log_likelihood(self):
ll = +self.gref.KL_divergence()
for g in self.bgplvms:
ll -= sparse_GP.log_likelihood(g)
return -ll
def _log_likelihood_gradients(self):
dLdmu, dLdS = reduce(lambda a, b: [a[0] + b[0], a[1] + b[1]], (g.dL_dmuS() for g in self.bgplvms))
dKLmu, dKLdS = self.gref.dKL_dmuS()
dLdmu -= dKLmu
dLdS -= dKLdS
dLdmuS = numpy.hstack((dLdmu.flatten(), dLdS.flatten())).flatten()
dldzt1 = reduce(lambda a, b: a + b, (sparse_GP._log_likelihood_gradients(g)[:self.MQ] for g in self.bgplvms))
return numpy.hstack((dLdmuS,
dldzt1,
numpy.hstack([numpy.hstack([g.dL_dtheta(),
g.likelihood._gradients(\
partial=g.partial_for_likelihood)]) \
for g in self.bgplvms])))
def plot_X(self):
fig = pylab.figure("MRD X", figsize=(4 * len(self.bgplvms), 3))
fig.clf()
for i, g in enumerate(self.bgplvms):
ax = fig.add_subplot(1, len(self.bgplvms), i + 1)
ax.imshow(g.X)
pylab.draw()
fig.tight_layout()
return fig
def plot_predict(self):
fig = pylab.figure("MRD Predictions", figsize=(4 * len(self.bgplvms), 3))
fig.clf()
for i, g in enumerate(self.bgplvms):
ax = fig.add_subplot(1, len(self.bgplvms), i + 1)
ax.imshow(g.predict(g.X)[0])
pylab.draw()
fig.tight_layout()
return fig
def plot_scales(self, *args, **kwargs):
fig = pylab.figure("MRD Scales", figsize=(4 * len(self.bgplvms), 3))
for i, g in enumerate(self.bgplvms):
ax = fig.add_subplot(1, len(self.bgplvms), i + 1)
g.kern.plot_ARD(ax=ax, *args, **kwargs)
pylab.draw()
fig.tight_layout()
return fig
def plot_latent(self, *args, **kwargs):
fig = pylab.figure("MRD Latent Spaces", figsize=(4 * len(self.bgplvms), 3))
for i, g in enumerate(self.bgplvms):
ax = fig.add_subplot(1, len(self.bgplvms), i + 1)
g.plot_latent(ax=ax, *args, **kwargs)
pylab.draw()
fig.tight_layout()
return fig

View file

@ -36,7 +36,7 @@ class sparse_GP(GP):
def __init__(self, X, likelihood, kernel, Z, X_variance=None, Xslices=None,Zslices=None, normalize_X=False):
self.scale_factor = 100.0# a scaling factor to help keep the algorithm stable
self.auto_scale_factor = False
self.Z = Z
self.Zslices = Zslices
self.Xslices = Xslices
@ -184,6 +184,12 @@ class sparse_GP(GP):
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._compute_kernel_matrices()
if self.auto_scale_factor:
if self.likelihood.is_heteroscedastic:
self.scale_factor = max(100.,(self.psi2_beta_scaled.sum(0).max()))
print self.scale_factor
else:
self.scale_factor = np.sqrt(self.psi2.sum(0).mean()*self.likelihood.precision)
self._computations()
def _get_params(self):

32
GPy/testing/mrd_tests.py Normal file
View file

@ -0,0 +1,32 @@
# Copyright (c) 2013, Max Zwiessele
# Licensed under the BSD 3-clause license (see LICENSE.txt)
'''
Created on 10 Apr 2013
@author: maxz
'''
import unittest
import numpy as np
import GPy
class MRDTests(unittest.TestCase):
def test_gradients(self):
num_m = 3
N, M, Q, D = 20, 8, 5, 50
X = np.random.rand(N, Q)
k = GPy.kern.linear(Q) + GPy.kern.bias(Q) + GPy.kern.white(Q)
K = k.K(X)
Ylist = [np.random.multivariate_normal(np.zeros(N), K, D).T for _ in range(num_m)]
m = GPy.models.MRD(*Ylist, Q=Q, kernel=k, M=M)
m.ensure_default_constraints()
m.randomize()
self.assertTrue(m.checkgrad())
if __name__ == "__main__":
print "Running unit tests, please be (very) patient..."
unittest.main()