[vardtc] missing data handling and stochastic update in d

This commit is contained in:
Max Zwiessele 2014-10-16 12:52:17 +01:00
parent 3358d06e42
commit 26396939e5
6 changed files with 124 additions and 37 deletions

View file

@ -10,6 +10,8 @@ from parameterization.variational import VariationalPosterior
import logging
from GPy.inference.latent_function_inference.posterior import Posterior
from GPy.inference.optimization.stochastics import SparseGPStochastics,\
SparseGPMissing
logger = logging.getLogger("sparse gp")
class SparseGP(GP):
@ -37,12 +39,7 @@ class SparseGP(GP):
def __init__(self, X, Y, Z, kernel, likelihood, inference_method=None,
name='sparse gp', Y_metadata=None, normalizer=False,
missing_data=False):
self.missing_data = missing_data
if self.missing_data:
self.ninan = ~np.isnan(Y)
missing_data=False, stochastic=False, batchsize=1):
#pick a sensible inference method
if inference_method is None:
if isinstance(likelihood, likelihoods.Gaussian):
@ -56,6 +53,22 @@ class SparseGP(GP):
self.num_inducing = Z.shape[0]
GP.__init__(self, X, Y, kernel, likelihood, inference_method=inference_method, name=name, Y_metadata=Y_metadata, normalizer=normalizer)
self.missing_data = missing_data
if stochastic and missing_data:
self.missing_data = True
self.ninan = ~np.isnan(Y)
self.stochastics = SparseGPStochastics(self, batchsize)
elif stochastic and not missing_data:
self.missing_data = False
self.stochastics = SparseGPStochastics(self, batchsize)
elif missing_data:
self.missing_data = True
self.ninan = ~np.isnan(Y)
self.stochastics = SparseGPMissing(self)
else:
self.stochastics = False
logger.info("Adding Z as parameter")
self.link_parameter(self.Z, index=0)
if self.missing_data:
@ -71,6 +84,7 @@ class SparseGP(GP):
print message,
print ''
self.posterior = None
def has_uncertain_inputs(self):
return isinstance(self.X, VariationalPosterior)
@ -156,7 +170,31 @@ class SparseGP(GP):
value_indices:
dictionary holding indices for the update in full_values.
if the key exists the update rule is:
if the key exists the update rule is:def df(x):
m.stochastics.do_stochastics()
grads = m._grads(x)
print '\r',
message = "Lik: {: 6.4E} Grad: {: 6.4E} Dim: {} Lik: {} Len: {!s}".format(float(m.log_likelihood()), np.einsum('i,i->', grads, grads), m.stochastics.d, float(m.likelihood.variance), " ".join(["{:3.2E}".format(l) for l in m.kern.lengthscale.values]))
print message,
return grads
def grad_stop(threshold):
def inner(args):
g = args['gradient']
return np.sqrt(np.einsum('i,i->',g,g)) < threshold
return inner
def maxiter_stop(maxiter):
def inner(args):
return args['n_iter'] == maxiter
return inner
def optimize(m, maxiter=1000):
#opt = climin.RmsProp(m.optimizer_array.copy(), df, 1e-6, decay=0.9, momentum=0.9, step_adapt=1e-7)
opt = climin.Adadelta(m.optimizer_array.copy(), df, 1e-2, decay=0.9)
ret = opt.minimize_until((grad_stop(.1), maxiter_stop(maxiter)))
print
return ret
full_values[key][value_indices[key]] += current_values[key]
"""
for key in current_values.keys():
@ -206,22 +244,29 @@ class SparseGP(GP):
def _outer_loop_for_missing_data(self):
Lm = None
dL_dKmm = None
Kmm = None
self._log_marginal_likelihood = 0
full_values = self._outer_init_full_values()
woodbury_inv = np.zeros((self.num_inducing, self.num_inducing, self.output_dim))
woodbury_vector = np.zeros((self.num_inducing, self.output_dim))
m_f = lambda i: "Inference with missing data: {: >7.2%}".format(float(i+1)/self.output_dim)
message = m_f(-1)
print message,
for d in xrange(self.output_dim):
if self.posterior is None:
woodbury_inv = np.zeros((self.num_inducing, self.num_inducing, self.output_dim))
woodbury_vector = np.zeros((self.num_inducing, self.output_dim))
else:
woodbury_inv = self.posterior._woodbury_inv
woodbury_vector = self.posterior._woodbury_vector
if not self.stochastics:
m_f = lambda i: "Inference with missing_data: {: >7.2%}".format(float(i+1)/self.output_dim)
message = m_f(-1)
print message,
for d in self.stochastics.d:
ninan = self.ninan[:, d]
print ' '*(len(message)) + '\r',
message = m_f(d)
print message,
if not self.stochastics:
print ' '*(len(message)) + '\r',
message = m_f(d)
print message,
posterior, log_marginal_likelihood, \
grad_dict, current_values, value_indices = self._inner_parameters_changed(
@ -236,19 +281,50 @@ class SparseGP(GP):
Lm = posterior.K_chol
dL_dKmm = grad_dict['dL_dKmm']
Kmm = posterior._K
woodbury_inv[:, :, d] = posterior.woodbury_inv
woodbury_vector[:, d:d+1] = posterior.woodbury_vector
self._log_marginal_likelihood += log_marginal_likelihood
print ''
if not self.stochastics:
print ''
self.posterior = Posterior(woodbury_inv=woodbury_inv, woodbury_vector=woodbury_vector,
K=Kmm, mean=None, cov=None, K_chol=Lm)
if self.posterior is None:
self.posterior = Posterior(woodbury_inv=woodbury_inv, woodbury_vector=woodbury_vector,
K=posterior._K, mean=None, cov=None, K_chol=posterior.K_chol)
self._outer_values_update(full_values)
def _outer_loop_without_missing_data(self):
self._log_marginal_likelihood = 0
if self.posterior is None:
woodbury_inv = np.zeros((self.num_inducing, self.num_inducing, self.output_dim))
woodbury_vector = np.zeros((self.num_inducing, self.output_dim))
else:
woodbury_inv = self.posterior._woodbury_inv
woodbury_vector = self.posterior._woodbury_vector
d = self.stochastics.d
posterior, log_marginal_likelihood, \
grad_dict, current_values, _ = self._inner_parameters_changed(
self.kern, self.X,
self.Z, self.likelihood,
self.Y_normalized[:, d], self.Y_metadata)
self.grad_dict = grad_dict
self._log_marginal_likelihood += log_marginal_likelihood
self._outer_values_update(current_values)
woodbury_inv[:, :, d] = posterior.woodbury_inv[:, :, None]
woodbury_vector[:, d] = posterior.woodbury_vector
if self.posterior is None:
self.posterior = Posterior(woodbury_inv=woodbury_inv, woodbury_vector=woodbury_vector,
K=posterior._K, mean=None, cov=None, K_chol=posterior.K_chol)
def parameters_changed(self):
if self.missing_data:
self._outer_loop_for_missing_data()
elif self.stochastics:
self._outer_loop_without_missing_data()
else:
self.posterior, self._log_marginal_likelihood, self.grad_dict, full_values, _ = self._inner_parameters_changed(self.kern, self.X, self.Z, self.likelihood, self.Y_normalized, self.Y_metadata)
self._outer_values_update(full_values)