deleted kernpart, prod and add seem to work okay.

This commit is contained in:
James Hensman 2014-02-19 17:37:18 +00:00
parent 493506408c
commit 92d71384b7
16 changed files with 95 additions and 238 deletions

View file

@ -70,7 +70,7 @@ class GP(Model):
def log_likelihood(self):
return self._log_marginal_likelihood
def _raw_predict(self, _Xnew, which_parts='all', full_cov=False, stop=False):
def _raw_predict(self, _Xnew, full_cov=False):
"""
Internal helper function for making predictions, does not account
for normalization or likelihood
@ -80,29 +80,27 @@ class GP(Model):
diagonal of the covariance is returned.
"""
Kx = self.kern.K(_Xnew, self.X, which_parts=which_parts).T
Kx = self.kern.K(_Xnew, self.X).T
#LiKx, _ = dtrtrs(self.posterior.woodbury_chol, np.asfortranarray(Kx), lower=1)
WiKx = np.dot(self.posterior.woodbury_inv, Kx)
mu = np.dot(Kx.T, self.posterior.woodbury_vector)
if full_cov:
Kxx = self.kern.K(_Xnew, which_parts=which_parts)
Kxx = self.kern.K(_Xnew)
#var = Kxx - tdot(LiKx.T)
var = np.dot(Kx.T, WiKx)
else:
Kxx = self.kern.Kdiag(_Xnew, which_parts=which_parts)
Kxx = self.kern.Kdiag(_Xnew)
#var = Kxx - np.sum(LiKx*LiKx, 0)
var = Kxx - np.sum(WiKx*Kx, 0)
var = var.reshape(-1, 1)
return mu, var
def predict(self, Xnew, which_parts='all', full_cov=False, **likelihood_args):
def predict(self, Xnew, full_cov=False, **likelihood_args):
"""
Predict the function(s) at the new point(s) Xnew.
:param Xnew: The points at which to make a prediction
:type Xnew: np.ndarray, Nnew x self.input_dim
:param which_parts: specifies which outputs kernel(s) to use in prediction
:type which_parts: ('all', list of bools)
:param full_cov: whether to return the full covariance matrix, or just
the diagonal
:type full_cov: bool
@ -118,13 +116,13 @@ class GP(Model):
"""
#predict the latent function values
mu, var = self._raw_predict(Xnew, full_cov=full_cov, which_parts=which_parts)
mu, var = self._raw_predict(Xnew, full_cov=full_cov)
# now push through likelihood
mean, var, _025pm, _975pm = self.likelihood.predictive_values(mu, var, full_cov, **likelihood_args)
return mean, var, _025pm, _975pm
def posterior_samples_f(self,X,size=10,which_parts='all',full_cov=True):
def posterior_samples_f(self,X,size=10, full_cov=True):
"""
Samples the posterior GP at the points X.
@ -132,13 +130,11 @@ class GP(Model):
:type X: np.ndarray, Nnew x self.input_dim.
:param size: the number of a posteriori samples.
:type size: int.
:param which_parts: which of the kernel functions to use (additively).
:type which_parts: 'all', or list of bools.
:param full_cov: whether to return the full covariance matrix, or just the diagonal.
:type full_cov: bool.
:returns: Ysim: set of simulations, a Numpy array (N x samples).
"""
m, v = self._raw_predict(X, which_parts=which_parts, full_cov=full_cov)
m, v = self._raw_predict(X, full_cov=full_cov)
v = v.reshape(m.size,-1) if len(v.shape)==3 else v
if not full_cov:
Ysim = np.random.multivariate_normal(m.flatten(), np.diag(v.flatten()), size).T
@ -147,7 +143,7 @@ class GP(Model):
return Ysim
def posterior_samples(self,X,size=10,which_parts='all',full_cov=True,noise_model=None):
def posterior_samples(self,X,size=10, full_cov=True,noise_model=None):
"""
Samples the posterior GP at the points X.
@ -155,15 +151,13 @@ class GP(Model):
:type X: np.ndarray, Nnew x self.input_dim.
:param size: the number of a posteriori samples.
:type size: int.
:param which_parts: which of the kernel functions to use (additively).
:type which_parts: 'all', or list of bools.
:param full_cov: whether to return the full covariance matrix, or just the diagonal.
:type full_cov: bool.
:param noise_model: for mixed noise likelihood, the noise model to use in the samples.
:type noise_model: integer.
:returns: Ysim: set of simulations, a Numpy array (N x samples).
"""
Ysim = self.posterior_samples_f(X, size, which_parts=which_parts, full_cov=full_cov)
Ysim = self.posterior_samples_f(X, size, full_cov=full_cov)
if isinstance(self.likelihood, Gaussian):
noise_std = np.sqrt(self.likelihood._get_params())
Ysim += np.random.normal(0,noise_std,Ysim.shape)

View file

@ -41,7 +41,7 @@ def coregionalization_toy2(optimize=True, plot=True):
Y = np.vstack((Y1, Y2))
#build the kernel
k1 = GPy.kern.rbf(1) + GPy.kern.bias(1)
k1 = GPy.kern.RBF(1) + GPy.kern.bias(1)
k2 = GPy.kern.coregionalize(2,1)
k = k1**k2
m = GPy.models.GPRegression(X, Y, kernel=k)
@ -68,7 +68,7 @@ def coregionalization_toy2(optimize=True, plot=True):
# Y2 = -np.sin(X2) + np.random.randn(*X2.shape) * 0.05
# Y = np.vstack((Y1, Y2))
#
# k1 = GPy.kern.rbf(1)
# k1 = GPy.kern.RBF(1)
# m = GPy.models.GPMultioutputRegression(X_list=[X1,X2],Y_list=[Y1,Y2],kernel_list=[k1])
# m.constrain_fixed('.*rbf_var', 1.)
# m.optimize(max_iters=100)
@ -127,7 +127,7 @@ def epomeo_gpx(max_iters=200, optimize=True, plot=True):
Z = np.hstack((np.linspace(t[:,0].min(), t[:, 0].max(), num_inducing)[:, None],
np.random.randint(0, 4, num_inducing)[:, None]))
k1 = GPy.kern.rbf(1)
k1 = GPy.kern.RBF(1)
k2 = GPy.kern.coregionalize(output_dim=5, rank=5)
k = k1**k2
@ -156,7 +156,7 @@ def multiple_optima(gene_number=937, resolution=80, model_restarts=10, seed=1000
data['Y'] = data['Y'] - np.mean(data['Y'])
lls = GPy.examples.regression._contour_data(data, length_scales, log_SNRs, GPy.kern.rbf)
lls = GPy.examples.regression._contour_data(data, length_scales, log_SNRs, GPy.kern.RBF)
if plot:
pb.contour(length_scales, log_SNRs, np.exp(lls), 20, cmap=pb.cm.jet)
ax = pb.gca()
@ -172,8 +172,8 @@ def multiple_optima(gene_number=937, resolution=80, model_restarts=10, seed=1000
optim_point_y = np.empty(2)
np.random.seed(seed=seed)
for i in range(0, model_restarts):
# kern = GPy.kern.rbf(1, variance=np.random.exponential(1.), lengthscale=np.random.exponential(50.))
kern = GPy.kern.rbf(1, variance=np.random.uniform(1e-3, 1), lengthscale=np.random.uniform(5, 50))
# kern = GPy.kern.RBF(1, variance=np.random.exponential(1.), lengthscale=np.random.exponential(50.))
kern = GPy.kern.RBF(1, variance=np.random.uniform(1e-3, 1), lengthscale=np.random.uniform(5, 50))
m = GPy.models.GPRegression(data['X'], data['Y'], kernel=kern)
m['noise_variance'] = np.random.uniform(1e-3, 1)
@ -196,7 +196,7 @@ def multiple_optima(gene_number=937, resolution=80, model_restarts=10, seed=1000
ax.set_ylim(ylim)
return m # (models, lls)
def _contour_data(data, length_scales, log_SNRs, kernel_call=GPy.kern.rbf):
def _contour_data(data, length_scales, log_SNRs, kernel_call=GPy.kern.RBF):
"""
Evaluate the GP objective function for a given data set for a range of
signal to noise ratios and a range of lengthscales.
@ -278,10 +278,10 @@ def toy_poisson_rbf_1d_laplace(optimize=True, plot=True):
optimizer='scg'
x_len = 30
X = np.linspace(0, 10, x_len)[:, None]
f_true = np.random.multivariate_normal(np.zeros(x_len), GPy.kern.rbf(1).K(X))
f_true = np.random.multivariate_normal(np.zeros(x_len), GPy.kern.RBF(1).K(X))
Y = np.array([np.random.poisson(np.exp(f)) for f in f_true])[:,None]
kern = GPy.kern.rbf(1)
kern = GPy.kern.RBF(1)
poisson_lik = GPy.likelihoods.Poisson()
laplace_inf = GPy.inference.latent_function_inference.LaplaceInference()
@ -319,10 +319,10 @@ def toy_ARD(max_iters=1000, kernel_type='linear', num_samples=300, D=4, optimize
if kernel_type == 'linear':
kernel = GPy.kern.linear(X.shape[1], ARD=1)
elif kernel_type == 'rbf_inv':
kernel = GPy.kern.rbf_inv(X.shape[1], ARD=1)
kernel = GPy.kern.RBF_inv(X.shape[1], ARD=1)
else:
kernel = GPy.kern.rbf(X.shape[1], ARD=1)
kernel += GPy.kern.white(X.shape[1]) + GPy.kern.bias(X.shape[1])
kernel = GPy.kern.RBF(X.shape[1], ARD=1)
kernel += GPy.kern.White(X.shape[1]) + GPy.kern.bias(X.shape[1])
m = GPy.models.GPRegression(X, Y, kernel)
# len_prior = GPy.priors.inverse_gamma(1,18) # 1, 25
# m.set_prior('.*lengthscale',len_prior)
@ -358,9 +358,9 @@ def toy_ARD_sparse(max_iters=1000, kernel_type='linear', num_samples=300, D=4, o
if kernel_type == 'linear':
kernel = GPy.kern.linear(X.shape[1], ARD=1)
elif kernel_type == 'rbf_inv':
kernel = GPy.kern.rbf_inv(X.shape[1], ARD=1)
kernel = GPy.kern.RBF_inv(X.shape[1], ARD=1)
else:
kernel = GPy.kern.rbf(X.shape[1], ARD=1)
kernel = GPy.kern.RBF(X.shape[1], ARD=1)
#kernel += GPy.kern.bias(X.shape[1])
X_variance = np.ones(X.shape) * 0.5
m = GPy.models.SparseGPRegression(X, Y, kernel, X_variance=X_variance)
@ -421,7 +421,7 @@ def sparse_GP_regression_1D(num_samples=400, num_inducing=5, max_iters=100, opti
X = np.random.uniform(-3., 3., (num_samples, 1))
Y = np.sin(X) + np.random.randn(num_samples, 1) * 0.05
# construct kernel
rbf = GPy.kern.rbf(1)
rbf = GPy.kern.RBF(1)
# create simple GP Model
m = GPy.models.SparseGPRegression(X, Y, kernel=rbf, num_inducing=num_inducing)
m.checkgrad(verbose=1)
@ -444,7 +444,7 @@ def sparse_GP_regression_2D(num_samples=400, num_inducing=50, max_iters=100, opt
Y[inan] = np.nan
# construct kernel
rbf = GPy.kern.rbf(2)
rbf = GPy.kern.RBF(2)
# create simple GP Model
m = GPy.models.SparseGPRegression(X, Y, kernel=rbf, num_inducing=num_inducing)
@ -476,9 +476,9 @@ def uncertain_inputs_sparse_regression(max_iters=200, optimize=True, plot=True):
# likelihood = GPy.likelihoods.Gaussian(Y)
Z = np.random.uniform(-3., 3., (7, 1))
k = GPy.kern.rbf(1)
k = GPy.kern.RBF(1)
# create simple GP Model - no input uncertainty on this one
m = GPy.models.SparseGPRegression(X, Y, kernel=GPy.kern.rbf(1), Z=Z)
m = GPy.models.SparseGPRegression(X, Y, kernel=GPy.kern.RBF(1), Z=Z)
if optimize:
m.optimize('scg', messages=1, max_iters=max_iters)
@ -489,7 +489,7 @@ def uncertain_inputs_sparse_regression(max_iters=200, optimize=True, plot=True):
print m
# the same Model with uncertainty
m = GPy.models.SparseGPRegression(X, Y, kernel=GPy.kern.rbf(1), Z=Z, X_variance=S)
m = GPy.models.SparseGPRegression(X, Y, kernel=GPy.kern.RBF(1), Z=Z, X_variance=S)
if optimize:
m.optimize('scg', messages=1, max_iters=max_iters)
if plot:

View file

@ -1,6 +1,7 @@
from _src.rbf import RBF
from _src.white import White
from _src.kern import Kern
Linear = 'foo'
#import bias
#import Brownian
#import coregionalize

View file

@ -5,8 +5,8 @@ import sys
import numpy as np
import itertools
from linear import Linear
from ..core.parameterization import Parameterized
from GPy.core.parameterization.param import Param
from ...core.parameterization import Parameterized
from ...core.parameterization.param import Param
from kern import Kern
class Add(Kern):
@ -27,7 +27,7 @@ class Add(Kern):
self.add_parameters(*subkerns)
def K(self, X, X2=None, which_parts='all'):
def K(self, X, X2=None):
"""
Compute the kernel function.
@ -35,52 +35,22 @@ class Add(Kern):
:param X2: (optional) the second set of arguments to the kernel. If X2
is None, this is passed throgh to the 'part' object, which
handles this as X2 == X.
:param which_parts: a list of booleans detailing whether to include
each of the part functions. By default, 'all'
indicates all parts
"""
if which_parts == 'all':
which_parts = [True] * self.size
assert X.shape[1] == self.input_dim
if X2 is None:
target = np.zeros((X.shape[0], X.shape[0]))
[p.K(X[:, i_s], None, target=target) for p, i_s, part_i_used in zip(self._parameters_, self.input_slices, which_parts) if part_i_used]
return sum([p.K(X[:, i_s], None) for p, i_s in zip(self._parameters_, self.input_slices)])
else:
target = np.zeros((X.shape[0], X2.shape[0]))
[p.K(X[:, i_s], X2[:, i_s], target=target) for p, i_s, part_i_used in zip(self._parameters_, self.input_slices, which_parts) if part_i_used]
return target
return sum([p.K(X[:, i_s], X2[:, i_s]) for p, i_s in zip(self._parameters_, self.input_slices)])
def update_gradients_full(self, dL_dK, X):
[p.update_gradients_full(dL_dK, X) for p in self._parameters_]
[p.update_gradients_full(dL_dK, X[:,i_s]) for p, i_s in zip(self._parameters_, self.input_slices)]
def update_gradients_sparse(self, dL_dKmm, dL_dKnm, dL_dKdiag, X, Z):
[p.update_gradients_sparse(dL_dKmm, dL_dKnm, dL_dKdiag, X, Z) for p in self._parameters_]
[p.update_gradients_sparse(dL_dKmm, dL_dKnm, dL_dKdiag, X[:,i_s], Z[:,i_s]) for p, i_s in zip(self._parameters_, i_s)]
def update_gradients_variational(self, dL_dKmm, dL_dpsi0, dL_dpsi1, dL_dpsi2, mu, S, Z):
[p.update_gradients_variational(dL_dKmm, dL_dpsi0, dL_dpsi1, dL_dpsi2, mu, S, Z) for p in self._parameters_]
def _param_grad_helper(self, dL_dK, X, X2=None):
"""
Compute the gradient of the covariance function with respect to the parameters.
:param dL_dK: An array of gradients of the objective function with respect to the covariance function.
:type dL_dK: Np.ndarray (num_samples x num_inducing)
:param X: Observed data inputs
:type X: np.ndarray (num_samples x input_dim)
:param X2: Observed data inputs (optional, defaults to X)
:type X2: np.ndarray (num_inducing x input_dim)
returns: dL_dtheta
"""
assert X.shape[1] == self.input_dim
target = np.zeros(self.size)
if X2 is None:
[p._param_grad_helper(dL_dK, X[:, i_s], None, target[ps]) for p, i_s, ps, in zip(self._parameters_, self.input_slices, self._param_slices_)]
else:
[p._param_grad_helper(dL_dK, X[:, i_s], X2[:, i_s], target[ps]) for p, i_s, ps, in zip(self._parameters_, self.input_slices, self._param_slices_)]
return self._transform_gradients(target)
def gradients_X(self, dL_dK, X, X2=None):
"""Compute the gradient of the objective function with respect to X.
@ -93,33 +63,15 @@ class Add(Kern):
target = np.zeros_like(X)
if X2 is None:
[p.gradients_X(dL_dK, X[:, i_s], None, target[:, i_s]) for p, i_s in zip(self._parameters_, self.input_slices)]
[np.add(target[:,i_s], p.gradients_X(dL_dK, X[:, i_s], None), target[:, i_s]) for p, i_s in zip(self._parameters_, self.input_slices)]
else:
[p.gradients_X(dL_dK, X[:, i_s], X2[:, i_s], target[:, i_s]) for p, i_s in zip(self._parameters_, self.input_slices)]
[np.add(target[:,i_s], p.gradients_X(dL_dK, X[:, i_s], X2[:,i_s]), target[:, i_s]) for p, i_s in zip(self._parameters_, self.input_slices)]
return target
def Kdiag(self, X, which_parts='all'):
def Kdiag(self, X):
"""Compute the diagonal of the covariance function for inputs X."""
if which_parts == 'all':
which_parts = [True] * self.size
assert X.shape[1] == self.input_dim
target = np.zeros(X.shape[0])
[p.Kdiag(X[:, i_s], target=target) for p, i_s, part_on in zip(self._parameters_, self.input_slices, which_parts) if part_on]
return target
def dKdiag_dtheta(self, dL_dKdiag, X):
"""Compute the gradient of the diagonal of the covariance function with respect to the parameters."""
assert X.shape[1] == self.input_dim
assert dL_dKdiag.size == X.shape[0]
target = np.zeros(self.size)
[p.dKdiag_dtheta(dL_dKdiag, X[:, i_s], target[ps]) for p, i_s, ps in zip(self._parameters_, self.input_slices, self._param_slices_)]
return self._transform_gradients(target)
def dKdiag_dX(self, dL_dKdiag, X):
assert X.shape[1] == self.input_dim
target = np.zeros_like(X)
[p.dKdiag_dX(dL_dKdiag, X[:, i_s], target[:, i_s]) for p, i_s in zip(self._parameters_, self.input_slices)]
return target
return sum([p.Kdiag(X[:, i_s]) for p, i_s in zip(self._parameters_, self.input_slices)])
def psi0(self, Z, mu, S):
target = np.zeros(mu.shape[0])

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@ -1,12 +1,12 @@
# Copyright (c) 2012, James Hensman and Ricardo Andrade
# Licensed under the BSD 3-clause license (see LICENSE.txt)
from kernpart import Kernpart
from kern import Kern
import numpy as np
from scipy import weave
from ...core.parameterization import Param
class Coregionalize(Kernpart):
class Coregionalize(Kern):
"""
Covariance function for intrinsic/linear coregionalization models
@ -133,6 +133,8 @@ class Coregionalize(Kernpart):
#dkappa = dL_dKdiag_small
#target += np.hstack([dW.flatten(),dkappa])
def gradients_X(self,dL_dK,X,X2,target):
#NOTE In this case, pass is equivalent to returning zero.
pass
def gradients_X(self,dL_dK,X,X2):
if X2 is None:
return np.zeros((X.shape[0], X.shape[0]))
else:
return np.zeros((X.shape[0], X2.shape[0]))

View file

@ -4,8 +4,8 @@
import sys
import numpy as np
import itertools
from ..core.parameterization import Parameterized
from GPy.core.parameterization.param import Param
from ...core.parameterization import Parameterized
from ...core.parameterization.param import Param
class Kern(Parameterized):

View file

@ -1,60 +0,0 @@
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
#from ...core.parameterized.Parameterized import set_as_parameter
from ...core.parameterization import Parameterized
class Kernpart_stationary(Kernpart):
def __init__(self, input_dim, lengthscale=None, ARD=False):
self.input_dim = input_dim
self.ARD = ARD
if not ARD:
self.num_params = 2
if lengthscale is not None:
self.lengthscale = np.asarray(lengthscale)
assert self.lengthscale.size == 1, "Only one lengthscale needed for non-ARD kernel"
else:
self.lengthscale = np.ones(1)
else:
self.num_params = self.input_dim + 1
if lengthscale is not None:
self.lengthscale = np.asarray(lengthscale)
assert self.lengthscale.size == self.input_dim, "bad number of lengthscales"
else:
self.lengthscale = np.ones(self.input_dim)
# initialize cache
self._Z, self._mu, self._S = np.empty(shape=(3, 1))
self._X, self._X2, self._parameters_ = np.empty(shape=(3, 1))
def _set_params(self, x):
self.lengthscale = x
self.lengthscale2 = np.square(self.lengthscale)
# reset cached results
self._X, self._X2, self._parameters_ = np.empty(shape=(3, 1))
self._Z, self._mu, self._S = np.empty(shape=(3, 1)) # cached versions of Z,mu,S
def dKdiag_dtheta(self, dL_dKdiag, X, target):
# For stationary covariances, derivative of diagonal elements
# wrt lengthscale is 0.
target[0] += np.sum(dL_dKdiag)
def dKdiag_dX(self, dL_dK, X, target):
pass # true for all stationary kernels
class Kernpart_inner(Kernpart):
def __init__(self,input_dim):
"""
The base class for a kernpart_inner: a positive definite function which forms part of a kernel that is based on the inner product between inputs.
:param input_dim: the number of input dimensions to the function
:type input_dim: int
Do not instantiate.
"""
Kernpart.__init__(self, input_dim)
# initialize cache
self._Z, self._mu, self._S = np.empty(shape=(3, 1))
self._X, self._X2, self._parameters_ = np.empty(shape=(3, 1))

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@ -5,10 +5,10 @@
import numpy as np
from scipy import weave
from kern import Kern
from ..util.linalg import tdot
from ..util.misc import fast_array_equal, param_to_array
from ..core.parameterization import Param
from ..core.parameterization.transformations import Logexp
from ...util.linalg import tdot
from ...util.misc import fast_array_equal, param_to_array
from ...core.parameterization import Param
from ...core.parameterization.transformations import Logexp
class Linear(Kern):
"""

View file

@ -35,64 +35,36 @@ class Prod(Kern):
self._X, self._X2 = np.empty(shape=(2,1))
self._params = None
def K(self,X,X2,target):
def K(self, X, X2=None):
self._K_computations(X,X2)
target += self._K1 * self._K2
def K1(self,X, X2):
"""Compute the part of the kernel associated with k1."""
self._K_computations(X, X2)
return self._K1
def K2(self, X, X2):
"""Compute the part of the kernel associated with k2."""
self._K_computations(X, X2)
return self._K2
return self._K1 * self._K2
def update_gradients_full(self, dL_dK, X):
self._K_computations(X, None)
self.k1.update_gradients_full(dL_dK*self._K2, X[:,self.slice1])
self.k2.update_gradients_full(dL_dK*self._K1, X[:,self.slice2])
def _param_grad_helper(self,dL_dK,X,X2,target):
"""Derivative of the covariance matrix with respect to the parameters."""
self._K_computations(X,X2)
if X2 is None:
self.k1._param_grad_helper(dL_dK*self._K2, X[:,self.slice1], None, target[:self.k1.num_params])
self.k2._param_grad_helper(dL_dK*self._K1, X[:,self.slice2], None, target[self.k1.num_params:])
else:
self.k1._param_grad_helper(dL_dK*self._K2, X[:,self.slice1], X2[:,self.slice1], target[:self.k1.num_params])
self.k2._param_grad_helper(dL_dK*self._K1, X[:,self.slice2], X2[:,self.slice2], target[self.k1.num_params:])
def Kdiag(self,X,target):
def Kdiag(self, X):
"""Compute the diagonal of the covariance matrix associated to X."""
target1 = np.zeros(X.shape[0])
target2 = np.zeros(X.shape[0])
self.k1.Kdiag(X[:,self.slice1],target1)
self.k2.Kdiag(X[:,self.slice2],target2)
target += target1 * target2
return self.k1.Kdiag(X[:,self.slice1]) * self.k2.Kdiag(X[:,self.slice2])
def update_gradients_sparse(self):
pass
#wtf goes here??
#def dKdiag_dtheta(self,dL_dKdiag,X,target):
#K1 = np.zeros(X.shape[0])
#K2 = np.zeros(X.shape[0])
#self.k1.Kdiag(X[:,self.slice1],K1)
#self.k2.Kdiag(X[:,self.slice2],K2)
#self.k1.dKdiag_dtheta(dL_dKdiag*K2,X[:,self.slice1],target[:self.k1.num_params])
#self.k2.dKdiag_dtheta(dL_dKdiag*K1,X[:,self.slice2],target[self.k1.num_params:])
def dKdiag_dtheta(self,dL_dKdiag,X,target):
K1 = np.zeros(X.shape[0])
K2 = np.zeros(X.shape[0])
self.k1.Kdiag(X[:,self.slice1],K1)
self.k2.Kdiag(X[:,self.slice2],K2)
self.k1.dKdiag_dtheta(dL_dKdiag*K2,X[:,self.slice1],target[:self.k1.num_params])
self.k2.dKdiag_dtheta(dL_dKdiag*K1,X[:,self.slice2],target[self.k1.num_params:])
def gradients_X(self,dL_dK,X,X2,target):
def gradients_X(self,dL_dK,X,X2):
"""derivative of the covariance matrix with respect to X."""
self._K_computations(X,X2)
if X2 is None:
if not isinstance(self.k1,Coregionalize) and not isinstance(self.k2,Coregionalize):
self.k1.gradients_X(dL_dK*self._K2, X[:,self.slice1], None, target[:,self.slice1])
self.k2.gradients_X(dL_dK*self._K1, X[:,self.slice2], None, target[:,self.slice2])
else:#if isinstance(self.k1,Coregionalize) or isinstance(self.k2,Coregionalize):
#NOTE The indices column in the inputs makes the ki.gradients_X fail when passing None instead of X[:,self.slicei]
X2 = X
self.k1.gradients_X(2.*dL_dK*self._K2, X[:,self.slice1], X2[:,self.slice1], target[:,self.slice1])
self.k2.gradients_X(2.*dL_dK*self._K1, X[:,self.slice2], X2[:,self.slice2], target[:,self.slice2])
self.k1.gradients_X(dL_dK*self._K2, X[:,self.slice1], None, target[:,self.slice1])
self.k2.gradients_X(dL_dK*self._K1, X[:,self.slice2], None, target[:,self.slice2])
else:
self.k1.gradients_X(dL_dK*self._K2, X[:,self.slice1], X2[:,self.slice1], target[:,self.slice1])
self.k2.gradients_X(dL_dK*self._K1, X[:,self.slice2], X2[:,self.slice2], target[:,self.slice2])
@ -112,14 +84,10 @@ class Prod(Kern):
self._params == self._get_params().copy()
if X2 is None:
self._X2 = None
self._K1 = np.zeros((X.shape[0],X.shape[0]))
self._K2 = np.zeros((X.shape[0],X.shape[0]))
self.k1.K(X[:,self.slice1],None,self._K1)
self.k2.K(X[:,self.slice2],None,self._K2)
self._K1 = self.k1.K(X[:,self.slice1],None)
self._K2 = self.k2.K(X[:,self.slice2],None)
else:
self._X2 = X2.copy()
self._K1 = np.zeros((X.shape[0],X2.shape[0]))
self._K2 = np.zeros((X.shape[0],X2.shape[0]))
self.k1.K(X[:,self.slice1],X2[:,self.slice1],self._K1)
self.k2.K(X[:,self.slice2],X2[:,self.slice2],self._K2)
self._K1 = self.k1.K(X[:,self.slice1],X2[:,self.slice1])
self._K2 = self.k2.K(X[:,self.slice2],X2[:,self.slice2])

View file

@ -5,10 +5,10 @@
import numpy as np
from scipy import weave
from kern import Kern
from ..util.linalg import tdot
from ..util.misc import fast_array_equal, param_to_array
from ..core.parameterization import Param
from ..core.parameterization.transformations import Logexp
from ...util.linalg import tdot
from ...util.misc import fast_array_equal, param_to_array
from ...core.parameterization import Param
from ...core.parameterization.transformations import Logexp
class RBF(Kern):
"""

View file

@ -3,8 +3,8 @@
from kern import Kern
import numpy as np
from ..core.parameterization import Param
from ..core.parameterization.transformations import Logexp
from ...core.parameterization import Param
from ...core.parameterization.transformations import Logexp
class White(Kern):
"""
@ -25,6 +25,8 @@ class White(Kern):
def K(self,X,X2):
if X2 is None:
return np.eye(X.shape[0])*self.variance
else:
return np.zeros((X.shape[0], X2.shape[0]))
def Kdiag(self,X):
ret = np.ones(X.shape[0])

View file

@ -23,7 +23,7 @@ class GPRegression(GP):
def __init__(self, X, Y, kernel=None):
if kernel is None:
kernel = kern.rbf(X.shape[1])
kernel = kern.RBF(X.shape[1])
likelihood = likelihoods.Gaussian()

View file

@ -7,7 +7,7 @@ from GPy.util.linalg import PCA
import numpy
import itertools
import pylab
from GPy.kern.kern import Kern
from GPy.kern import Kern
from GPy.models.bayesian_gplvm import BayesianGPLVM
class MRD(Model):

View file

@ -7,7 +7,7 @@ import pylab as pb
import Tango
from matplotlib.textpath import TextPath
from matplotlib.transforms import offset_copy
from ...kern.linear import Linear
from ...kern import Linear
def plot_ARD(kernel, fignum=None, ax=None, title='', legend=False):

View file

@ -9,7 +9,7 @@ from ...util.misc import param_to_array
def plot_fit(model, plot_limits=None, which_data_rows='all',
which_data_ycols='all', which_parts='all', fixed_inputs=[],
which_data_ycols='all', fixed_inputs=[],
levels=20, samples=0, fignum=None, ax=None, resolution=None,
plot_raw=False,
linecol=Tango.colorsHex['darkBlue'],fillcol=Tango.colorsHex['lightBlue']):
@ -20,7 +20,7 @@ def plot_fit(model, plot_limits=None, which_data_rows='all',
- In higher dimensions, use fixed_inputs to plot the GP with some of the inputs fixed.
Can plot only part of the data and part of the posterior functions
using which_data_rowsm which_data_ycols and which_parts
using which_data_rowsm which_data_ycols.
:param plot_limits: The limits of the plot. If 1D [xmin,xmax], if 2D [[xmin,ymin],[xmax,ymax]]. Defaluts to data limits
:type plot_limits: np.array
@ -28,8 +28,6 @@ def plot_fit(model, plot_limits=None, which_data_rows='all',
:type which_data_rows: 'all' or a slice object to slice model.X, model.Y
:param which_data_ycols: when the data has several columns (independant outputs), only plot these
:type which_data_rows: 'all' or a list of integers
:param which_parts: which of the kernel functions to plot (additively)
:type which_parts: 'all', or list of bools
:param fixed_inputs: a list of tuple [(i,v), (i,v)...], specifying that input index i should be set to value v.
:type fixed_inputs: a list of tuples
:param resolution: the number of intervals to sample the GP on. Defaults to 200 in 1D and 50 (a 50x50 grid) in 2D
@ -76,12 +74,12 @@ def plot_fit(model, plot_limits=None, which_data_rows='all',
#make a prediction on the frame and plot it
if plot_raw:
m, v = model._raw_predict(Xgrid, which_parts=which_parts)
m, v = model._raw_predict(Xgrid)
lower = m - 2*np.sqrt(v)
upper = m + 2*np.sqrt(v)
Y = model.Y
else:
m, v, lower, upper = model.predict(Xgrid, which_parts=which_parts)
m, v, lower, upper = model.predict(Xgrid)
Y = model.Y
for d in which_data_ycols:
gpplot(Xnew, m[:, d], lower[:, d], upper[:, d], axes=ax, edgecol=linecol, fillcol=fillcol)
@ -89,7 +87,7 @@ def plot_fit(model, plot_limits=None, which_data_rows='all',
#optionally plot some samples
if samples: #NOTE not tested with fixed_inputs
Ysim = model.posterior_samples(Xgrid, samples, which_parts=which_parts)
Ysim = model.posterior_samples(Xgrid, samples)
for yi in Ysim.T:
ax.plot(Xnew, yi[:,None], Tango.colorsHex['darkBlue'], linewidth=0.25)
#ax.plot(Xnew, yi[:,None], marker='x', linestyle='--',color=Tango.colorsHex['darkBlue']) #TODO apply this line for discrete outputs.
@ -131,10 +129,10 @@ def plot_fit(model, plot_limits=None, which_data_rows='all',
#predict on the frame and plot
if plot_raw:
m, _ = model._raw_predict(Xgrid, which_parts=which_parts)
m, _ = model._raw_predict(Xgrid)
Y = model.Y
else:
m, _, _, _ = model.predict(Xgrid, which_parts=which_parts)
m, _, _, _ = model.predict(Xgrid)
Y = model.data
for d in which_data_ycols:
m_d = m[:,d].reshape(resolution, resolution).T

View file

@ -513,8 +513,8 @@ def toy_rbf_1d(seed=default_seed, num_samples=500):
num_in = 1
X = np.random.uniform(low= -1.0, high=1.0, size=(num_samples, num_in))
X.sort(axis=0)
rbf = GPy.kern.rbf(num_in, variance=1., lengthscale=np.array((0.25,)))
white = GPy.kern.white(num_in, variance=1e-2)
rbf = GPy.kern.RBF(num_in, variance=1., lengthscale=np.array((0.25,)))
white = GPy.kern.White(num_in, variance=1e-2)
kernel = rbf + white
K = kernel.K(X)
y = np.reshape(np.random.multivariate_normal(np.zeros(num_samples), K), (num_samples, 1))