GPy/GPy/likelihoods/noise_model_constructors.py
Alan Saul 8343615098 Integrated Laplace and merged Merge remote-tracking branch 'gpy_real/devel' into merge_branch
Conflicts:
	GPy/core/gp.py
	GPy/likelihoods/__init__.py
	GPy/likelihoods/likelihood_functions.py
	GPy/likelihoods/link_functions.py
2013-10-03 16:52:02 +01:00

115 lines
3.6 KiB
Python

# Copyright (c) 2013, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
import noise_models
def binomial(gp_link=None):
"""
Construct a binomial likelihood
:param gp_link: a GPy gp_link function
"""
if gp_link is None:
gp_link = noise_models.gp_transformations.Probit()
#else:
# assert isinstance(gp_link,noise_models.gp_transformations.GPTransformation), 'gp_link function is not valid.'
if isinstance(gp_link,noise_models.gp_transformations.Probit):
analytical_mean = True
analytical_variance = False
elif isinstance(gp_link,noise_models.gp_transformations.Heaviside):
analytical_mean = True
analytical_variance = True
else:
analytical_mean = False
analytical_variance = False
return noise_models.binomial_noise.Binomial(gp_link,analytical_mean,analytical_variance)
def exponential(gp_link=None):
"""
Construct a binomial likelihood
:param gp_link: a GPy gp_link function
"""
if gp_link is None:
gp_link = noise_models.gp_transformations.Identity()
analytical_mean = False
analytical_variance = False
return noise_models.exponential_noise.Exponential(gp_link,analytical_mean,analytical_variance)
def gaussian_ep(gp_link=None,variance=1.):
"""
Construct a gaussian likelihood
:param gp_link: a GPy gp_link function
:param variance: scalar
"""
if gp_link is None:
gp_link = noise_models.gp_transformations.Identity()
#else:
# assert isinstance(gp_link,noise_models.gp_transformations.GPTransformation), 'gp_link function is not valid.'
analytical_mean = False
analytical_variance = False
return noise_models.gaussian_noise.Gaussian(gp_link,analytical_mean,analytical_variance,variance)
def poisson(gp_link=None):
"""
Construct a Poisson likelihood
:param gp_link: a GPy gp_link function
"""
if gp_link is None:
gp_link = noise_models.gp_transformations.Log_ex_1()
#else:
# assert isinstance(gp_link,noise_models.gp_transformations.GPTransformation), 'gp_link function is not valid.'
analytical_mean = False
analytical_variance = False
return noise_models.poisson_noise.Poisson(gp_link,analytical_mean,analytical_variance)
def gamma(gp_link=None,beta=1.):
"""
Construct a Gamma likelihood
:param gp_link: a GPy gp_link function
:param beta: scalar
"""
if gp_link is None:
gp_link = noise_models.gp_transformations.Log_ex_1()
analytical_mean = False
analytical_variance = False
return noise_models.gamma_noise.Gamma(gp_link,analytical_mean,analytical_variance,beta)
def gaussian(gp_link=None, variance=2, D=None, N=None):
"""
Construct a Gaussian likelihood
:param gp_link: a GPy gp_link function
:param variance: scalar, variance
"""
if gp_link is None:
gp_link = noise_models.gp_transformations.Identity()
analytical_mean = True
analytical_variance = True # ?
return noise_models.gaussian_noise.Gaussian(gp_link, analytical_mean,
analytical_variance, variance=variance, D=D, N=N)
def student_t(gp_link=None, deg_free=5, sigma2=2):
"""
Construct a Student t likelihood
:param gp_link: a GPy gp_link function
:param deg_free: scalar, degrees of freedom
:param sigma2: scalar, variance
"""
if gp_link is None:
gp_link = noise_models.gp_transformations.Identity()
analytical_mean = True
analytical_variance = True
return noise_models.student_t_noise.StudentT(gp_link, analytical_mean,
analytical_variance,deg_free, sigma2)