Tidying up laplace_tests.py

This commit is contained in:
Alan Saul 2013-10-16 18:42:36 +01:00
parent 6e28fdf4fd
commit 208b6862bd
2 changed files with 305 additions and 275 deletions

View file

@ -415,7 +415,10 @@ class NoiseDistribution(object):
raise NotImplementedError
def dlogpdf_link_dtheta(self, link_f, y, extra_data=None):
raise NotImplementedError
if len(self._get_params()) == 0:
pass
else:
raise NotImplementedError
def dlogpdf_dlink_dtheta(self, link_f, y, extra_data=None):
raise NotImplementedError
@ -474,7 +477,7 @@ class NoiseDistribution(object):
:type y: Nx1 array
:param extra_data: extra_data which is not used in student t distribution - not used
:returns: derivative of log likelihood evaluated for this point
:rtype: float
:rtype: 1xN array
"""
link_f = self.gp_link.transf(f)
dlogpdf_dlink = self.dlogpdf_dlink(link_f, y, extra_data=extra_data)
@ -494,8 +497,8 @@ class NoiseDistribution(object):
:param y: data
:type y: Nx1 array
:param extra_data: extra_data which is not used in student t distribution - not used
:returns: second derivative of log likelihood evaluated for this point
:rtype: float
:returns: second derivative of log likelihood evaluated for this point (diagonal only)
:rtype: 1xN array
"""
link_f = self.gp_link.transf(f)
d2logpdf_dlink2 = self.d2logpdf_dlink2(link_f, y, extra_data=extra_data)

View file

@ -63,7 +63,305 @@ def dparam_checkgrad(func, dfunc, params, args, constrain_positive=True, randomi
return gradchecking
from nose.tools import with_setup
class TestNoiseModels(object):
"""
Generic model checker
"""
def setUp(self):
self.N = 5
self.D = 3
self.X = np.random.rand(self.N, self.D)*10
self.real_std = 0.1
noise = np.random.randn(*self.X[:, 0].shape)*self.real_std
self.Y = (np.sin(self.X[:, 0]*2*np.pi) + noise)[:, None]
self.f = np.random.rand(self.N, 1)
self.var = 0.2
self.var = np.random.rand(1)
#Make a bigger step as lower bound can be quite curved
self.step = 1e-3
def tearDown(self):
self.Y = None
self.f = None
self.X = None
def test_noise_models(self):
self.setUp()
"""
Dictionary where we nest models we would like to check
Name: {
"model": model_instance,
"grad_params": {
"names": [names_of_params_we_want, to_grad_check],
"vals": [values_of_params, to_start_at],
"constrain_positive": [boolean_values, of_whether_to_constrain]
},
"laplace": boolean_of_whether_model_should_work_for_laplace
}
"""
noise_models = {"Student_t_default": {
"model": GPy.likelihoods.student_t(deg_free=5, sigma2=self.var),
"grad_params": {
"names": ["t_noise"],
"vals": [self.var],
"constrain_positive": [True]
},
"laplace": True
},
"Student_t_small_var": {
"model": GPy.likelihoods.student_t(deg_free=5, sigma2=self.var),
"grad_params": {
"names": ["t_noise"],
"vals": [0.01],
"constrain_positive": [True]
},
"laplace": True
},
"Student_t_approx_gauss": {
"model": GPy.likelihoods.student_t(deg_free=1000, sigma2=self.var),
"grad_params": {
"names": ["t_noise"],
"vals": [self.var],
"constrain_positive": [True]
},
"laplace": True
},
"Student_t_log": {
"model": GPy.likelihoods.student_t(gp_link=gp_transformations.Log(), deg_free=5, sigma2=self.var),
"grad_params": {
"names": ["t_noise"],
"vals": [self.var],
"constrain_positive": [True]
},
"laplace": True
},
"Gaussian_default": {
"model": GPy.likelihoods.gaussian(variance=self.var, D=self.D, N=self.N),
"grad_params": {
"names": ["noise_model_variance"],
"vals": [self.var],
"constrain_positive": [True]
},
"laplace": True
},
"Gaussian_log": {
"model": GPy.likelihoods.gaussian(gp_link=gp_transformations.Log(), variance=self.var, D=self.D, N=self.N),
"grad_params": {
"names": ["noise_model_variance"],
"vals": [self.var],
"constrain_positive": [True]
},
"laplace": True
}
}
for name, attributes in noise_models.iteritems():
model = attributes["model"]
params = attributes["grad_params"]
param_vals = params["vals"]
param_names= params["names"]
constrain_positive = params["constrain_positive"]
laplace = attributes["laplace"]
if len(param_vals) > 1:
raise NotImplementedError("Cannot support multiple params in likelihood yet!")
#Required by all
#Normal derivatives
yield self.t_logpdf, model
yield self.t_dlogpdf_df, model
yield self.t_d2logpdf_df2, model
#Link derivatives
yield self.t_dlogpdf_dlink, model
yield self.t_d2logpdf_dlink2, model
yield self.t_d3logpdf_dlink3, model
if laplace:
#Laplace only derivatives
yield self.t_d3logpdf_df3, model
#Params
yield self.t_dlogpdf_dparams, model, param_vals
yield self.t_dlogpdf_df_dparams, model, param_vals
yield self.t_d2logpdf2_df2_dparams, model, param_vals
#Link params
yield self.t_dlogpdf_link_dparams, model, param_vals
yield self.t_dlogpdf_dlink_dparams, model, param_vals
yield self.t_d2logpdf2_dlink2_dparams, model, param_vals
#laplace likelihood gradcheck
yield self.t_laplace_fit_rbf_white, model, param_vals, param_names, constrain_positive
self.tearDown()
#############
# dpdf_df's #
#############
@with_setup(setUp, tearDown)
def t_logpdf(self, model):
print "\n{}".format(inspect.stack()[0][3])
np.testing.assert_almost_equal(
np.log(model.pdf(self.f.copy(), self.Y.copy())),
model.logpdf(self.f.copy(), self.Y.copy()))
@with_setup(setUp, tearDown)
def t_dlogpdf_df(self, model):
print "\n{}".format(inspect.stack()[0][3])
self.description = "\n{}".format(inspect.stack()[0][3])
logpdf = functools.partial(model.logpdf, y=self.Y)
dlogpdf_df = functools.partial(model.dlogpdf_df, y=self.Y)
grad = GradientChecker(logpdf, dlogpdf_df, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
assert grad.checkgrad()
@with_setup(setUp, tearDown)
def t_d2logpdf_df2(self, model):
print "\n{}".format(inspect.stack()[0][3])
dlogpdf_df = functools.partial(model.dlogpdf_df, y=self.Y)
d2logpdf_df2 = functools.partial(model.d2logpdf_df2, y=self.Y)
grad = GradientChecker(dlogpdf_df, d2logpdf_df2, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
assert grad.checkgrad()
@with_setup(setUp, tearDown)
def t_d3logpdf_df3(self, model):
print "\n{}".format(inspect.stack()[0][3])
d2logpdf_df2 = functools.partial(model.d2logpdf_df2, y=self.Y)
d3logpdf_df3 = functools.partial(model.d3logpdf_df3, y=self.Y)
grad = GradientChecker(d2logpdf_df2, d3logpdf_df3, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
assert grad.checkgrad()
##############
# df_dparams #
##############
@with_setup(setUp, tearDown)
def t_dlogpdf_dparams(self, model, params):
print "\n{}".format(inspect.stack()[0][3])
assert (
dparam_checkgrad(model.logpdf, model.dlogpdf_dtheta,
params, args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
@with_setup(setUp, tearDown)
def t_dlogpdf_df_dparams(self, model, params):
print "\n{}".format(inspect.stack()[0][3])
assert (
dparam_checkgrad(model.dlogpdf_df, model.dlogpdf_df_dtheta,
params, args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
@with_setup(setUp, tearDown)
def t_d2logpdf2_df2_dparams(self, model, params):
print "\n{}".format(inspect.stack()[0][3])
assert (
dparam_checkgrad(model.d2logpdf_df2, model.d2logpdf_df2_dtheta,
params, args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
################
# dpdf_dlink's #
################
@with_setup(setUp, tearDown)
def t_dlogpdf_dlink(self, model):
print "\n{}".format(inspect.stack()[0][3])
logpdf = functools.partial(model.logpdf_link, y=self.Y)
dlogpdf_dlink = functools.partial(model.dlogpdf_dlink, y=self.Y)
grad = GradientChecker(logpdf, dlogpdf_dlink, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
assert grad.checkgrad()
@with_setup(setUp, tearDown)
def t_d2logpdf_dlink2(self, model):
print "\n{}".format(inspect.stack()[0][3])
dlogpdf_dlink = functools.partial(model.dlogpdf_dlink, y=self.Y)
d2logpdf_dlink2 = functools.partial(model.d2logpdf_dlink2, y=self.Y)
grad = GradientChecker(dlogpdf_dlink, d2logpdf_dlink2, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
assert grad.checkgrad()
@with_setup(setUp, tearDown)
def t_d3logpdf_dlink3(self, model):
print "\n{}".format(inspect.stack()[0][3])
d2logpdf_dlink2 = functools.partial(model.d2logpdf_dlink2, y=self.Y)
d3logpdf_dlink3 = functools.partial(model.d3logpdf_dlink3, y=self.Y)
grad = GradientChecker(d2logpdf_dlink2, d3logpdf_dlink3, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
assert grad.checkgrad()
#################
# dlink_dparams #
#################
@with_setup(setUp, tearDown)
def t_dlogpdf_link_dparams(self, model, params):
print "\n{}".format(inspect.stack()[0][3])
assert (
dparam_checkgrad(model.logpdf_link, model.dlogpdf_link_dtheta,
params, args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
@with_setup(setUp, tearDown)
def t_dlogpdf_dlink_dparams(self, model, params):
print "\n{}".format(inspect.stack()[0][3])
assert (
dparam_checkgrad(model.dlogpdf_dlink, model.dlogpdf_dlink_dtheta,
params, args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
@with_setup(setUp, tearDown)
def t_d2logpdf2_dlink2_dparams(self, model, params):
print "\n{}".format(inspect.stack()[0][3])
assert (
dparam_checkgrad(model.d2logpdf_dlink2, model.d2logpdf_dlink2_dtheta,
params, args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
################
# laplace test #
################
@with_setup(setUp, tearDown)
def t_laplace_fit_rbf_white(self, model, param_vals, param_names, constrain_positive):
print "\n{}".format(inspect.stack()[0][3])
self.Y = self.Y/self.Y.max()
white_var = 0.001
kernel = GPy.kern.rbf(self.X.shape[1]) + GPy.kern.white(self.X.shape[1])
laplace_likelihood = GPy.likelihoods.Laplace(self.Y.copy(), model)
m = GPy.models.GPRegression(self.X, self.Y.copy(), kernel, likelihood=laplace_likelihood)
m.ensure_default_constraints()
m.constrain_fixed('white', white_var)
for param_num in range(len(param_names)):
name = param_names[param_num]
if constrain_positive[param_num]:
m.constrain_positive(name)
m[name] = param_vals[param_num]
m.randomize()
m.checkgrad(verbose=1, step=self.step)
print m
assert m.checkgrad(step=self.step)
class LaplaceTests(unittest.TestCase):
"""
Specific likelihood tests, not general enough for the above tests
"""
def setUp(self):
self.N = 5
self.D = 3
@ -90,116 +388,6 @@ class LaplaceTests(unittest.TestCase):
self.f = None
self.X = None
def test_mass_logpdf(self):
print "\n{}".format(inspect.stack()[0][3])
np.testing.assert_almost_equal(
np.log(self.gauss.pdf(self.f.copy(), self.Y.copy())),
self.gauss.logpdf(self.f.copy(), self.Y.copy()))
""" dGauss_df's """
def test_gaussian_dlogpdf_df(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
logpdf = functools.partial(self.gauss.logpdf, y=self.Y)
dlogpdf_df = functools.partial(self.gauss.dlogpdf_df, y=self.Y)
grad = GradientChecker(logpdf, dlogpdf_df, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_gaussian_d2logpdf_df2(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
dlogpdf_df = functools.partial(self.gauss.dlogpdf_df, y=self.Y)
d2logpdf_df2 = functools.partial(self.gauss.d2logpdf_df2, y=self.Y)
grad = GradientChecker(dlogpdf_df, d2logpdf_df2, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_gaussian_d3logpdf_df3(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
d2logpdf_df2 = functools.partial(self.gauss.d2logpdf_df2, y=self.Y)
d3logpdf_df3 = functools.partial(self.gauss.d3logpdf_df3, y=self.Y)
grad = GradientChecker(d2logpdf_df2, d3logpdf_df3, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_gaussian_dlogpdf_df_dvar(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.gauss.dlogpdf_df, self.gauss.dlogpdf_df_dtheta,
[self.var], args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
def test_gaussian_d2logpdf2_df2_dvar(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.gauss.d2logpdf_df2, self.gauss.d2logpdf_df2_dtheta,
[self.var], args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
""" dGauss_dlink's """
def test_gaussian_dlogpdf_dlink(self):
print "\n{}".format(inspect.stack()[0][3])
logpdf = functools.partial(self.gauss.logpdf_link, y=self.Y)
dlogpdf_dlink = functools.partial(self.gauss.dlogpdf_dlink, y=self.Y)
grad = GradientChecker(logpdf, dlogpdf_dlink, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_gaussian_d2logpdf_dlink2(self):
print "\n{}".format(inspect.stack()[0][3])
dlogpdf_dlink = functools.partial(self.gauss.dlogpdf_dlink, y=self.Y)
d2logpdf_dlink2 = functools.partial(self.gauss.d2logpdf_dlink2, y=self.Y)
grad = GradientChecker(dlogpdf_dlink, d2logpdf_dlink2, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_gaussian_d3logpdf_dlink3(self):
print "\n{}".format(inspect.stack()[0][3])
d2logpdf_dlink2 = functools.partial(self.gauss.d2logpdf_dlink2, y=self.Y)
d3logpdf_dlink3 = functools.partial(self.gauss.d3logpdf_dlink3, y=self.Y)
grad = GradientChecker(d2logpdf_dlink2, d3logpdf_dlink3, self.f.copy(), 'g')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_gaussian_dlogpdf_dvar(self):
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.gauss.logpdf, self.gauss.dlogpdf_dtheta,
[self.var], args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
def test_gaussian_dlogpdf_dlink_dvar(self):
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.gauss.dlogpdf_dlink, self.gauss.dlogpdf_dlink_dtheta,
[self.var], args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
def test_gaussian_d2logpdf2_dlink2_dvar(self):
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.gauss.d2logpdf_dlink2, self.gauss.d2logpdf_dlink2_dtheta,
[self.var], args=(self.f, self.Y), constrain_positive=True,
randomize=False, verbose=True)
)
""" Gradchecker fault """
@unittest.expectedFailure
def test_gaussian_d2logpdf_df2_2(self):
@ -223,167 +411,6 @@ class LaplaceTests(unittest.TestCase):
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
""" dStudentT_df's """
def test_studentt_dlogpdf_df(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
link = functools.partial(self.stu_t.logpdf, y=self.Y)
dlogpdf_df = functools.partial(self.stu_t.dlogpdf_df, y=self.Y)
grad = GradientChecker(link, dlogpdf_df, self.f.copy(), 'f')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_studentt_d2logpdf_df2(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
dlogpdf_df = functools.partial(self.stu_t.dlogpdf_df, y=self.Y)
d2logpdf_df2 = functools.partial(self.stu_t.d2logpdf_df2, y=self.Y)
grad = GradientChecker(dlogpdf_df, d2logpdf_df2, self.f.copy(), 'f')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_studentt_d3lik_d3f(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
d2logpdf_df2 = functools.partial(self.stu_t.d2logpdf_df2, y=self.Y)
d3logpdf_df3 = functools.partial(self.stu_t.d3logpdf_df3, y=self.Y)
grad = GradientChecker(d2logpdf_df2, d3logpdf_df3, self.f.copy(), 'f')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_studentt_dlogpdf_df_dvar(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.stu_t.dlogpdf_df, self.stu_t.dlogpdf_df_dtheta,
[self.var], args=(self.f.copy(), self.Y.copy()),
constrain_positive=True, randomize=True, verbose=True)
)
def test_studentt_d2logpdf_df2_dvar(self):
#FIXME: Needs non-identity Link function
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.stu_t.d2logpdf_df2, self.stu_t.d2logpdf_df2_dtheta,
[self.var], args=(self.f.copy(), self.Y.copy()),
constrain_positive=True, randomize=True, verbose=True)
)
""" dStudentT_dlink's """
def test_studentt_dlogpdf_dlink(self):
print "\n{}".format(inspect.stack()[0][3])
logpdf = functools.partial(self.stu_t.logpdf, y=self.Y)
dlogpdf_dlink = functools.partial(self.stu_t.dlogpdf_dlink, y=self.Y)
grad = GradientChecker(logpdf, dlogpdf_dlink, self.f.copy(), 'f')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_studentt_d2logpdf_dlink2(self):
print "\n{}".format(inspect.stack()[0][3])
dlogpdf_dlink = functools.partial(self.stu_t.dlogpdf_dlink, y=self.Y)
d2logpdf_dlink2 = functools.partial(self.stu_t.d2logpdf_dlink2, y=self.Y)
grad = GradientChecker(dlogpdf_dlink, d2logpdf_dlink2, self.f.copy(), 'f')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_studentt_d3logpdf_dlink3(self):
print "\n{}".format(inspect.stack()[0][3])
d2logpdf_dlink2 = functools.partial(self.stu_t.d2logpdf_dlink2, y=self.Y)
d3logpdf_dlink3 = functools.partial(self.stu_t.d3logpdf_dlink3, y=self.Y)
grad = GradientChecker(d2logpdf_dlink2, d3logpdf_dlink3, self.f.copy(), 'f')
grad.randomize()
grad.checkgrad(verbose=1)
self.assertTrue(grad.checkgrad())
def test_studentt_dlogpdf_dvar(self):
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.stu_t.logpdf, self.stu_t.dlogpdf_dtheta,
[self.var], args=(self.f.copy(), self.Y.copy()),
constrain_positive=True, randomize=True, verbose=True)
)
def test_studentt_dlogpdf_dlink_dvar(self):
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.stu_t.dlogpdf_dlink, self.stu_t.dlogpdf_dlink_dtheta,
[self.var], args=(self.f.copy(), self.Y.copy()),
constrain_positive=True, randomize=True, verbose=True)
)
def test_studentt_d2logpdf_dlink2_dvar(self):
print "\n{}".format(inspect.stack()[0][3])
self.assertTrue(
dparam_checkgrad(self.stu_t.d2logpdf_dlink2, self.stu_t.d2logpdf_dlink2_dtheta,
[self.var], args=(self.f.copy(), self.Y.copy()),
constrain_positive=True, randomize=True, verbose=True)
)
""" Grad check whole models (grad checking Laplace not just noise models """
def test_gauss_rbf(self):
print "\n{}".format(inspect.stack()[0][3])
self.Y = self.Y/self.Y.max()
kernel = GPy.kern.rbf(self.X.shape[1]) + GPy.kern.white(self.X.shape[1])
gauss_laplace = GPy.likelihoods.Laplace(self.Y.copy(), self.gauss)
m = GPy.models.GPRegression(self.X, self.Y.copy(), kernel, likelihood=gauss_laplace)
m.ensure_default_constraints()
m.randomize()
m.checkgrad(verbose=1, step=self.step)
self.assertTrue(m.checkgrad(step=self.step))
def test_studentt_approx_gauss_rbf(self):
print "\n{}".format(inspect.stack()[0][3])
self.Y = self.Y/self.Y.max()
self.stu_t = GPy.likelihoods.student_t(deg_free=1000, sigma2=self.var)
kernel = GPy.kern.rbf(self.X.shape[1]) + GPy.kern.white(self.X.shape[1])
stu_t_laplace = GPy.likelihoods.Laplace(self.Y.copy(), self.stu_t)
m = GPy.models.GPRegression(self.X, self.Y.copy(), kernel, likelihood=stu_t_laplace)
m.ensure_default_constraints()
m.constrain_positive('t_noise')
m.randomize()
m.checkgrad(verbose=1, step=self.step)
print m
self.assertTrue(m.checkgrad(step=self.step))
def test_studentt_rbf(self):
print "\n{}".format(inspect.stack()[0][3])
self.Y = self.Y/self.Y.max()
white_var = 0.001
kernel = GPy.kern.rbf(self.X.shape[1]) + GPy.kern.white(self.X.shape[1])
stu_t_laplace = GPy.likelihoods.Laplace(self.Y.copy(), self.stu_t)
m = GPy.models.GPRegression(self.X, self.Y.copy(), kernel, likelihood=stu_t_laplace)
m.ensure_default_constraints()
m.constrain_positive('t_noise')
m.constrain_fixed('white', white_var)
m.randomize()
m.checkgrad(verbose=1, step=self.step)
print m
self.assertTrue(m.checkgrad(step=self.step))
""" With small variances its likely the implicit part isn't perfectly correct? """
@unittest.expectedFailure
def test_studentt_rbf_smallvar(self):
print "\n{}".format(inspect.stack()[0][3])
self.Y = self.Y/self.Y.max()
white_var = 0.001
kernel = GPy.kern.rbf(self.X.shape[1]) + GPy.kern.white(self.X.shape[1])
stu_t_laplace = GPy.likelihoods.Laplace(self.Y.copy(), self.stu_t)
m = GPy.models.GPRegression(self.X, self.Y.copy(), kernel, likelihood=stu_t_laplace)
m.ensure_default_constraints()
m.constrain_positive('t_noise')
m.constrain_fixed('white', white_var)
m['t_noise'] = 0.01
m.randomize()
m.checkgrad(verbose=1)
print m
self.assertTrue(m.checkgrad(step=self.step))
if __name__ == "__main__":
print "Running unit tests"
unittest.main()