removing testing code from kern.py (it's now in kern_tests.py

This commit is contained in:
James Hensman 2014-02-25 15:49:45 +00:00
parent 3a0a192362
commit 6a667e749f

View file

@ -124,210 +124,3 @@ class Kern(Parameterized):
assert isinstance(other, Kern), "only kernels can be added to kernels..." assert isinstance(other, Kern), "only kernels can be added to kernels..."
from prod import Prod from prod import Prod
return Prod(self, other, tensor) return Prod(self, other, tensor)
from GPy.core.model import Model
class Kern_check_model(Model):
"""This is a dummy model class used as a base class for checking that the gradients of a given kernel are implemented correctly. It enables checkgrad() to be called independently on a kernel."""
def __init__(self, kernel=None, dL_dK=None, X=None, X2=None):
from GPy.kern import RBF
Model.__init__(self, 'kernel_test_model')
num_samples = 20
num_samples2 = 10
if kernel==None:
kernel = RBF(1)
if X==None:
X = np.random.randn(num_samples, kernel.input_dim)
if dL_dK==None:
if X2==None:
dL_dK = np.ones((X.shape[0], X.shape[0]))
else:
dL_dK = np.ones((X.shape[0], X2.shape[0]))
self.kernel=kernel
self.add_parameter(kernel)
self.X = X
self.X2 = X2
self.dL_dK = dL_dK
def is_positive_definite(self):
v = np.linalg.eig(self.kernel.K(self.X))[0]
if any(v<-10*sys.float_info.epsilon):
return False
else:
return True
def log_likelihood(self):
return (self.dL_dK*self.kernel.K(self.X, self.X2)).sum()
def _log_likelihood_gradients(self):
raise NotImplementedError, "This needs to be implemented to use the kern_check_model class."
class Kern_check_dK_dtheta(Kern_check_model):
"""This class allows gradient checks for the gradient of a kernel with respect to parameters. """
def __init__(self, kernel=None, dL_dK=None, X=None, X2=None):
Kern_check_model.__init__(self,kernel=kernel,dL_dK=dL_dK, X=X, X2=X2)
def _log_likelihood_gradients(self):
target = np.zeros_like(self._get_params())
self.kernel._param_grad_helper(self.dL_dK, self.X, self.X2, target)
return target
class Kern_check_dKdiag_dtheta(Kern_check_model):
"""This class allows gradient checks of the gradient of the diagonal of a kernel with respect to the parameters."""
def __init__(self, kernel=None, dL_dK=None, X=None):
Kern_check_model.__init__(self,kernel=kernel,dL_dK=dL_dK, X=X, X2=None)
if dL_dK==None:
self.dL_dK = np.ones((self.X.shape[0]))
def parameters_changed(self):
self.kernel.update_gradients_full(self.dL_dK, self.X)
def log_likelihood(self):
return (self.dL_dK*self.kernel.Kdiag(self.X)).sum()
def _log_likelihood_gradients(self):
return self.kernel.dKdiag_dtheta(self.dL_dK, self.X)
class Kern_check_dK_dX(Kern_check_model):
"""This class allows gradient checks for the gradient of a kernel with respect to X. """
def __init__(self, kernel=None, dL_dK=None, X=None, X2=None):
Kern_check_model.__init__(self,kernel=kernel,dL_dK=dL_dK, X=X, X2=X2)
self.remove_parameter(kernel)
self.X = Param('X', self.X)
self.add_parameter(self.X)
def _log_likelihood_gradients(self):
return self.kernel.gradients_X(self.dL_dK, self.X, self.X2).flatten()
class Kern_check_dKdiag_dX(Kern_check_dK_dX):
"""This class allows gradient checks for the gradient of a kernel diagonal with respect to X. """
def __init__(self, kernel=None, dL_dK=None, X=None, X2=None):
Kern_check_dK_dX.__init__(self,kernel=kernel,dL_dK=dL_dK, X=X, X2=None)
if dL_dK==None:
self.dL_dK = np.ones((self.X.shape[0]))
def log_likelihood(self):
return (self.dL_dK*self.kernel.Kdiag(self.X)).sum()
def _log_likelihood_gradients(self):
return self.kernel.dKdiag_dX(self.dL_dK, self.X).flatten()
def kern_test(kern, X=None, X2=None, output_ind=None, verbose=False):
"""
This function runs on kernels to check the correctness of their
implementation. It checks that the covariance function is positive definite
for a randomly generated data set.
:param kern: the kernel to be tested.
:type kern: GPy.kern.Kernpart
:param X: X input values to test the covariance function.
:type X: ndarray
:param X2: X2 input values to test the covariance function.
:type X2: ndarray
"""
pass_checks = True
if X==None:
X = np.random.randn(10, kern.input_dim)
if output_ind is not None:
X[:, output_ind] = np.random.randint(kern.output_dim, X.shape[0])
if X2==None:
X2 = np.random.randn(20, kern.input_dim)
if output_ind is not None:
X2[:, output_ind] = np.random.randint(kern.output_dim, X2.shape[0])
if verbose:
print("Checking covariance function is positive definite.")
result = Kern_check_model(kern, X=X).is_positive_definite()
if result and verbose:
print("Check passed.")
if not result:
print("Positive definite check failed for " + kern.name + " covariance function.")
pass_checks = False
return False
if verbose:
print("Checking gradients of K(X, X) wrt theta.")
result = Kern_check_dK_dtheta(kern, X=X, X2=None).checkgrad(verbose=verbose)
if result and verbose:
print("Check passed.")
if not result:
print("Gradient of K(X, X) wrt theta failed for " + kern.name + " covariance function. Gradient values as follows:")
Kern_check_dK_dtheta(kern, X=X, X2=None).checkgrad(verbose=True)
pass_checks = False
return False
if verbose:
print("Checking gradients of K(X, X2) wrt theta.")
result = Kern_check_dK_dtheta(kern, X=X, X2=X2).checkgrad(verbose=verbose)
if result and verbose:
print("Check passed.")
if not result:
print("Gradient of K(X, X) wrt theta failed for " + kern.name + " covariance function. Gradient values as follows:")
Kern_check_dK_dtheta(kern, X=X, X2=X2).checkgrad(verbose=True)
pass_checks = False
return False
if verbose:
print("Checking gradients of Kdiag(X) wrt theta.")
result = Kern_check_dKdiag_dtheta(kern, X=X).checkgrad(verbose=verbose)
if result and verbose:
print("Check passed.")
if not result:
print("Gradient of Kdiag(X) wrt theta failed for " + kern.name + " covariance function. Gradient values as follows:")
Kern_check_dKdiag_dtheta(kern, X=X).checkgrad(verbose=True)
pass_checks = False
return False
if verbose:
print("Checking gradients of K(X, X) wrt X.")
try:
result = Kern_check_dK_dX(kern, X=X, X2=None).checkgrad(verbose=verbose)
except NotImplementedError:
result=True
if verbose:
print("gradients_X not implemented for " + kern.name)
if result and verbose:
print("Check passed.")
if not result:
print("Gradient of K(X, X) wrt X failed for " + kern.name + " covariance function. Gradient values as follows:")
Kern_check_dK_dX(kern, X=X, X2=None).checkgrad(verbose=True)
pass_checks = False
return False
if verbose:
print("Checking gradients of K(X, X2) wrt X.")
try:
result = Kern_check_dK_dX(kern, X=X, X2=X2).checkgrad(verbose=verbose)
except NotImplementedError:
result=True
if verbose:
print("gradients_X not implemented for " + kern.name)
if result and verbose:
print("Check passed.")
if not result:
print("Gradient of K(X, X) wrt X failed for " + kern.name + " covariance function. Gradient values as follows:")
Kern_check_dK_dX(kern, X=X, X2=X2).checkgrad(verbose=True)
pass_checks = False
return False
if verbose:
print("Checking gradients of Kdiag(X) wrt X.")
try:
result = Kern_check_dKdiag_dX(kern, X=X).checkgrad(verbose=verbose)
except NotImplementedError:
result=True
if verbose:
print("gradients_X not implemented for " + kern.name)
if result and verbose:
print("Check passed.")
if not result:
print("Gradient of Kdiag(X) wrt X failed for " + kern.name + " covariance function. Gradient values as follows:")
Kern_check_dKdiag_dX(kern, X=X).checkgrad(verbose=True)
pass_checks = False
return False
return pass_checks