Multioutput models added

This commit is contained in:
Ricardo 2013-08-02 20:10:02 +01:00
parent 1c2a4c5c64
commit 4c7ebb6601
9 changed files with 251 additions and 62 deletions

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@ -173,7 +173,7 @@ class GP(GPBase):
This is to allow for different normalizations of the output dimensions.
"""
assert isinstance(self.likelihood,EP_Mixed_Noise)
assert hasattr(self,'multioutput')
index = np.ones_like(Xnew)*output
Xnew = np.hstack((Xnew,index))
@ -182,7 +182,10 @@ class GP(GPBase):
mu, var = self._raw_predict(Xnew, full_cov=full_cov, which_parts=which_parts)
# now push through likelihood
if isinstance(self.likelihood,EP_Mixed_Noise):
mean, var, _025pm, _975pm = self.likelihood.predictive_values(mu, var, full_cov, noise_model = output)
else:
mean, var, _025pm, _975pm = self.likelihood_list[output].predictive_values(mu, var, full_cov)
return mean, var, _025pm, _975pm
def _raw_predict_single_output(self, _Xnew, output=0, which_parts='all', full_cov=False,stop=False):

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@ -106,13 +106,16 @@ class GPBase(Model):
gpplot(Xnew, m, m - 2 * np.sqrt(np.diag(v)[:, None]), m + 2 * np.sqrt(np.diag(v))[:, None, ], axes=ax)
for i in range(samples):
ax.plot(Xnew, Ysim[i, :], Tango.colorsHex['darkBlue'], linewidth=0.25)
#ax.plot(self.X[which_data], self.likelihood.Y[which_data], 'kx', mew=1.5)
#ax.plot(Xu[which_data], self.likelihood.Y[self.likelihood.index==output][:,None], 'kx', mew=1.5)
ax.set_xlim(xmin, xmax)
ymin, ymax = min(np.append(self.likelihood.Y, m - 2 * np.sqrt(np.diag(v)[:, None]))), max(np.append(self.likelihood.Y, m + 2 * np.sqrt(np.diag(v)[:, None])))
ymin, ymax = ymin - 0.1 * (ymax - ymin), ymax + 0.1 * (ymax - ymin)
ax.set_ylim(ymin, ymax)
if hasattr(self,'Z'):
Zu = self.Z[self.Z[:,-1]==output,:]
Zu = self.Z * self._Xscale + self._Xoffset
Zu = self.Z[self.Z[:,-1]==output ,0:1] #??
ax.plot(Zu, np.zeros_like(Zu) + ax.get_ylim()[0], 'r|', mew=1.5, markersize=12)
else:
raise NotImplementedError, "Cannot define a frame with more than two input dimensions"
@ -132,7 +135,7 @@ class GPBase(Model):
fig = pb.figure(num=fignum)
ax = fig.add_subplot(111)
if self.X.shape[1] == 1 and not isinstance(self.likelihood,EP_Mixed_Noise):
if self.X.shape[1] == 1 and not hasattr(self,'multioutput'):
Xu = self.X * self._Xscale + self._Xoffset # NOTE self.X are the normalized values now
@ -146,7 +149,7 @@ class GPBase(Model):
ax.set_xlim(xmin, xmax)
ax.set_ylim(ymin, ymax)
elif self.X.shape[1] == 2 and not isinstance(self.likelihood,EP_Mixed_Noise): # FIXME
elif self.X.shape[1] == 2 and not hasattr(self,'multioutput'):
resolution = resolution or 50
Xnew, _, _, xmin, xmax = x_frame2D(self.X, plot_limits, resolution)
x, y = np.linspace(xmin[0], xmax[0], resolution), np.linspace(xmin[1], xmax[1], resolution)
@ -158,17 +161,23 @@ class GPBase(Model):
ax.set_xlim(xmin[0], xmax[0])
ax.set_ylim(xmin[1], xmax[1])
elif self.X.shape[1] == 2 and isinstance(self.likelihood,EP_Mixed_Noise):
Xu = self.X[self.X[:,-1]==output,:]
elif self.X.shape[1] == 2 and hasattr(self,'multioutput'):
Xu = self.X[self.X[:,-1]==output,:] #keep the output of interest
Xu = self.X * self._Xscale + self._Xoffset
Xu = self.X[self.X[:,-1]==output ,0:1]
Xu = self.X[self.X[:,-1]==output ,0:1] #get rid of the index column
Xnew, xmin, xmax = x_frame1D(Xu, plot_limits=plot_limits)
m, _, lower, upper = self.predict_single_output(Xnew, which_parts=which_parts,output=output)
#if not isinstance(self.likelihood,EP_Mixed_Noise):
# m, _, lower, upper = self.predict(np.hstack([Xnew,np.repeat(output,Xnew.size)[:,None]]), which_parts=which_parts)
#else:
# m, _, lower, upper = self.predict_single_output(Xnew, which_parts=which_parts,output=output)
for d in range(m.shape[1]):
gpplot(Xnew, m[:, d], lower[:, d], upper[:, d], axes=ax)
#ax.plot(Xu[which_data], self.likelihood.data[which_data, d], 'kx', mew=1.5)
ax.plot(Xu[which_data], self.likelihood.data[self.likelihood.index==output][:,None], 'kx', mew=1.5)
#ax.plot(Xu[which_data], self.likelihood.data[self.likelihood.index==output][:,None], 'kx', mew=1.5)
ax.plot(Xu[which_data], self.likelihood_list[output].data, 'kx', mew=1.5)
ymin, ymax = min(np.append(self.likelihood.data, lower)), max(np.append(self.likelihood.data, upper))
ymin, ymax = ymin - 0.1 * (ymax - ymin), ymax + 0.1 * (ymax - ymin)
ax.set_xlim(xmin, xmax)

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@ -293,7 +293,7 @@ class SparseGP(GPBase):
return mean, var, _025pm, _975pm
def plot(self, samples=0, plot_limits=None, which_data='all', which_parts='all', resolution=None, levels=20, fignum=None, ax=None):
def plot(self, samples=0, plot_limits=None, which_data='all', which_parts='all', resolution=None, levels=20, fignum=None, ax=None, output=None):
if ax is None:
fig = pb.figure(num=fignum)
ax = fig.add_subplot(111)
@ -301,8 +301,8 @@ class SparseGP(GPBase):
if which_data is 'all':
which_data = slice(None)
GPBase.plot(self, samples=0, plot_limits=None, which_data='all', which_parts='all', resolution=None, levels=20, ax=ax)
if self.X.shape[1] == 1:
GPBase.plot(self, samples=0, plot_limits=plot_limits, which_data='all', which_parts='all', resolution=None, levels=20, ax=ax, output=output)
if self.X.shape[1] == 1 and not hasattr(self,'multioutput'):
if self.has_uncertain_inputs:
Xu = self.X * self._Xscale + self._Xoffset # NOTE self.X are the normalized values now
ax.errorbar(Xu[which_data, 0], self.likelihood.data[which_data, 0],
@ -311,10 +311,31 @@ class SparseGP(GPBase):
Zu = self.Z * self._Xscale + self._Xoffset
ax.plot(Zu, np.zeros_like(Zu) + ax.get_ylim()[0], 'r|', mew=1.5, markersize=12)
elif self.X.shape[1] == 2:
elif self.X.shape[1] == 2 and not hasattr(self,'multioutput'):
Zu = self.Z * self._Xscale + self._Xoffset
ax.plot(Zu[:, 0], Zu[:, 1], 'wo')
elif self.X.shape[1] == 2 and hasattr(self,'multioutput'):
Xu = self.X[self.X[:,-1]==output,:]
if self.has_uncertain_inputs:
Xu = self.X * self._Xscale + self._Xoffset # NOTE self.X are the normalized values now
Xu = self.X[self.X[:,-1]==output ,0:1] #??
ax.errorbar(Xu[which_data, 0], self.likelihood.data[which_data, 0],
xerr=2 * np.sqrt(self.X_variance[which_data, 0]),
ecolor='k', fmt=None, elinewidth=.5, alpha=.5)
Zu = self.Z[self.Z[:,-1]==output,:]
Zu = self.Z * self._Xscale + self._Xoffset
Zu = self.Z[self.Z[:,-1]==output ,0:1] #??
ax.plot(Zu, np.zeros_like(Zu) + ax.get_ylim()[0], 'r|', mew=1.5, markersize=12)
#ax.set_ylim(ax.get_ylim()[0],)
else:
raise NotImplementedError, "Cannot define a frame with more than two input dimensions"
def predict_single_output(self, Xnew, output=0, which_parts='all', full_cov=False):
"""
@ -336,7 +357,7 @@ class SparseGP(GPBase):
This is to allow for different normalizations of the output dimensions.
"""
assert isinstance(self.likelihood,EP_Mixed_Noise)
assert hasattr(self,'multioutput')
index = np.ones_like(Xnew)*output
Xnew = np.hstack((Xnew,index))
@ -345,6 +366,51 @@ class SparseGP(GPBase):
mu, var = self._raw_predict(Xnew, full_cov=full_cov, which_parts=which_parts)
# now push through likelihood
if isinstance(self.likelihood,EP_Mixed_Noise):
mean, var, _025pm, _975pm = self.likelihood.predictive_values(mu, var, full_cov, noise_model = output)
else:
mean, var, _025pm, _975pm = self.likelihood_list[output].predictive_values(mu, var, full_cov)
return mean, var, _025pm, _975pm
def _raw_predict_single_output(self, _Xnew, output=0, X_variance_new=None, which_parts='all', full_cov=False,stop=False):
"""
Internal helper function for making predictions, does not account
for normalization or likelihood
"""
Bi, _ = dpotri(self.LB, lower=0) # WTH? this lower switch should be 1, but that doesn't work!
symmetrify(Bi)
Kmmi_LmiBLmi = backsub_both_sides(self.Lm, np.eye(self.num_inducing) - Bi)
if self.Cpsi1V is None:
psi1V = np.dot(self.psi1.T,self.likelihood.V)
tmp, _ = dtrtrs(self.Lm, np.asfortranarray(psi1V), lower=1, trans=0)
tmp, _ = dpotrs(self.LB, tmp, lower=1)
self.Cpsi1V, _ = dtrtrs(self.Lm, tmp, lower=1, trans=1)
assert hasattr(self,'multioutput')
index = np.ones_like(_Xnew)*output
_Xnew = np.hstack((_Xnew,index))
if X_variance_new is None:
Kx = self.kern.K(self.Z, _Xnew, which_parts=which_parts)
mu = np.dot(Kx.T, self.Cpsi1V)
if full_cov:
Kxx = self.kern.K(_Xnew, which_parts=which_parts)
var = Kxx - mdot(Kx.T, Kmmi_LmiBLmi, Kx) # NOTE this won't work for plotting
else:
Kxx = self.kern.Kdiag(_Xnew, which_parts=which_parts)
var = Kxx - np.sum(Kx * np.dot(Kmmi_LmiBLmi, Kx), 0)
else:
# assert which_p.Tarts=='all', "swithching out parts of variational kernels is not implemented"
Kx = self.kern.psi1(self.Z, _Xnew, X_variance_new) # , which_parts=which_parts) TODO: which_parts
mu = np.dot(Kx, self.Cpsi1V)
if full_cov:
raise NotImplementedError, "TODO"
else:
Kxx = self.kern.psi0(self.Z, _Xnew, X_variance_new)
psi2 = self.kern.psi2(self.Z, _Xnew, X_variance_new)
var = Kxx - np.sum(np.sum(psi2 * Kmmi_LmiBLmi[None, :, :], 1), 1)
return mu, var[:, None]

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@ -18,7 +18,7 @@ class Prod(Kernpart):
"""
def __init__(self,k1,k2,tensor=False):
self.num_params = k1.num_params + k2.num_params
self.name = k1.name + '<times>' + k2.name
self.name = '['+k1.name + '(x)' + k2.name +']'
self.k1 = k1
self.k2 = k2
if tensor:

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@ -249,7 +249,7 @@ class EP_Mixed_Noise(likelihood):
self.tau_[i] = 1./Sigma_diag[i] - self.eta*self.tau_tilde[i]
self.v_[i] = mu[i]/Sigma_diag[i] - self.eta*self.v_tilde[i]
#Marginal moments
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.noise_model.moments_match(self._transf_data[i],self.tau_[i],self.v_[i])
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.noise_model_list[self.index[i]].moments_match(self._transf_data[i],self.tau_[i],self.v_[i])
#Site parameters update
Delta_tau = self.delta/self.eta*(1./sigma2_hat[i] - 1./Sigma_diag[i])
Delta_v = self.delta/self.eta*(mu_hat[i]/sigma2_hat[i] - mu[i]/Sigma_diag[i])
@ -344,7 +344,7 @@ class EP_Mixed_Noise(likelihood):
self.tau_[i] = 1./Sigma_diag[i] - self.eta*self.tau_tilde[i]
self.v_[i] = mu[i]/Sigma_diag[i] - self.eta*self.v_tilde[i]
#Marginal moments
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.noise_model.moments_match(self._transf_data[i],self.tau_[i],self.v_[i])
self.Z_hat[i], mu_hat[i], sigma2_hat[i] = self.noise_model_list[self.index[i]].moments_match(self._transf_data[i],self.tau_[i],self.v_[i])
#Site parameters update
Delta_tau = self.delta/self.eta*(1./sigma2_hat[i] - 1./Sigma_diag[i])
Delta_v = self.delta/self.eta*(mu_hat[i]/sigma2_hat[i] - mu[i]/Sigma_diag[i])

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@ -6,6 +6,7 @@ import numpy as np
from ..core import GP
from .. import likelihoods
from .. import kern
from ..util import multioutput
import pylab as pb
@ -29,7 +30,7 @@ class GPMultioutput(GP):
"""
def __init__(self,X_list,Y_list,noise_list=[],kernel_list=None,normalize_X=False,normalize_Y=False,W=1): #TODO W
def __init__(self,X_list,Y_list,kernel_list=None,normalize_X=False,normalize_Y=False,W=1,mixed_noise_list=[]): #TODO W
assert len(X_list) == len(Y_list)
index = []
@ -40,53 +41,30 @@ class GPMultioutput(GP):
i += 1
index = np.vstack(index)
if noise_list == []:
likelihood_list = []
self.likelihood_list = []
if mixed_noise_list == []:
for Y in Y_list:
likelihood_list.append(likelihoods.Gaussian(Y,normalize = normalize_Y))
self.likelihood_list.append(likelihoods.Gaussian(Y,normalize = normalize_Y))
Y = np.vstack([l_.Y for l_ in likelihood_list])
Y = np.vstack([l_.Y for l_ in self.likelihood_list])
likelihood = likelihoods.Gaussian(Y,normalize=False)
likelihood.index = index
else:
assert len(Y_list) == len(mixed_noise_list)
for noise,Y in zip(mixed_noise_list,Y_list):
self.likelihood_list.append(likelihoods.EP(Y,noise))
likelihood = likelihoods.EP_Mixed_Noise(Y_list, mixed_noise_list)
X = np.hstack([np.vstack(X_list),index])
original_dim = X.shape[1] - 1
if kernel_list is None:
original_dim = X.shape[1]-1
kernel_list = [kern.rbf(original_dim) + kern.white(original_dim)]
kernel_list = [[kern.rbf(original_dim)],[kern.white(original_dim+1)]]
mkernel = multioutput.build_cor_kernel(input_dim=original_dim, Nout=len(X_list), CK = kernel_list[0], NC = kernel_list[1], W=1)
mkernel = kernel_list[0].prod(kern.coregionalise(len(X_list),W),tensor=True)
for k in kernel_list[1:]:
mkernel += k.prod(kern.coregionalise(len(X_list),W),tensor=True)
self.multioutput = True
GP.__init__(self, X, likelihood, mkernel, normalize_X=normalize_X)
self.ensure_default_constraints()
"""
if likelihood is None:
noise_model_list = []
for Y in Y_list:
noise_model_list.append(likelihoods.Gaussian(Y,normalize = normalize_Y))
#noise_model_list = [likelihoods.gaussian(variance=1.) for Y in Y_list]
#likelihood = likelihoods.EP_Mixed_Noise(Y_list, noise_model_list)
elif Y_list is not None:
if not all(np.vstack(Y_list).flatten() == likelihood.data.flatten()):
raise Warning, 'likelihood.data and Y_list values are different.'
X = np.hstack([np.vstack(X_list),likelihood.index])
if kernel_list is None:
original_dim = X.shape[1]-1
kernel_list = [kern.rbf(original_dim) + kern.white(original_dim)]
mkernel = kernel_list[0].prod(kern.coregionalise(len(X_list),W),tensor=True) #TODO W
for k in kernel_list[1:]:
mkernel += k.prod(kern.coregionalise(len(X_list),W),tensor=True) #TODO W
#kern1 = kern.rbf(1) + kern.white(1)
#kern2 = kern.coregionalise(2,1)
#kern3 = kern1.prod(kern2,tensor=True)
"""

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@ -0,0 +1,97 @@
# Copyright (c) 2013, Ricardo Andrade
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
from ..core import SparseGP
from .. import likelihoods
from .. import kern
from ..util import multioutput
import pylab as pb
class SparseGPMultioutput(SparseGP):
"""
Multiple output Gaussian process
This is a thin wrapper around the models.GP class, with a set of sensible defaults
:param X_list: input observations
:param Y_list: observed values
:param L_list: a GPy likelihood, defaults to Binomial with probit link_function
:param kernel_list: a GPy kernel, defaults to rbf
:param normalize_X: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_X: False|True
:param normalize_Y: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_Y: False|True
.. Note:: Multiple independent outputs are allowed using columns of Y
"""
def __init__(self,X_list,Y_list,kernel_list=None,normalize_X=False,normalize_Y=False,Z_list=None,num_inducing_list=10,X_variance=None,W=1,mixed_noise_list=[]): #TODO W
assert len(X_list) == len(Y_list)
index = []
for x,y,j in zip(X_list,Y_list,range(len(X_list))):
assert x.shape[0] == y.shape[0]
index.append(np.repeat(j,y.size)[:,None])
index = np.vstack(index)
self.likelihood_list = []
if mixed_noise_list == []:
for Y in Y_list:
self.likelihood_list.append(likelihoods.Gaussian(Y,normalize = normalize_Y))
Y = np.vstack([l_.Y for l_ in self.likelihood_list])
likelihood = likelihoods.Gaussian(Y,normalize=False)
likelihood.index = index
else:
assert len(Y_list) == len(mixed_noise_list)
for noise,Y in zip(mixed_noise_list,Y_list):
self.likelihood_list.append(likelihoods.EP(Y,noise))
likelihood = likelihoods.EP_Mixed_Noise(Y_list, mixed_noise_list)
"""
if noise_list == []:
self.likelihood_list = []
for Y in Y_list:
self.likelihood_list.append(likelihoods.Gaussian(Y,normalize = normalize_Y))
Y = np.vstack([l_.Y for l_ in self.likelihood_list])
likelihood = likelihoods.Gaussian(Y,normalize=False)
likelihood.index = index
"""
X = np.hstack([np.vstack(X_list),index])
original_dim = X.shape[1] - 1
if kernel_list is None:
kernel_list = [[kern.rbf(original_dim)],[kern.white(original_dim+1)]]
mkernel = multioutput.build_cor_kernel(input_dim=original_dim, Nout=len(X_list), CK = kernel_list[0], NC = kernel_list[1], W=1)
z_index = []
if Z_list is None:
if isinstance(num_inducing_list,int):
num_inducing_list = [num_inducing_list for Xj in X_list]
Z_list = []
for Xj,nj,j in zip(X_list,num_inducing_list,range(len(X_list))):
i = np.random.permutation(Xj.shape[0])[:nj]
z_index.append(np.repeat(j,nj)[:,None])
Z_list.append(Xj[i].copy())
else:
assert len(Z_list) == len(X_list)
for Zj,Xj,j in zip(Z_list,X_list,range(len(Z_list))):
assert Zj.shape[1] == Xj.shape[1]
z_index.append(np.repeat(j,Zj.shape[0])[:,None])
Z = np.hstack([np.vstack(Z_list),np.vstack(z_index)])
self.multioutput = True
SparseGP.__init__(self, X, likelihood, mkernel, Z=Z, normalize_X=normalize_X, X_variance=X_variance)
self.constrain_fixed('.*iip_\d+_1')
self.ensure_default_constraints()

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@ -14,3 +14,4 @@ import mocap
import visualize
import decorators
import classification
import multioutput

35
GPy/util/multioutput.py Normal file
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@ -0,0 +1,35 @@
import numpy as np
import warnings
from .. import kern
def build_cor_kernel(input_dim, Nout, CK = [], NC = [], W=1):
"""
Builds an appropiate coregionalized kernel
:input_dim: Input dimensionality
:Nout: Number of outputs
:param CK: List of coregionalized kernels (i.e., this will be multiplied by a coregionalise kernel).
:param K: List of kernels that won't be multiplied by a coregionalise kernel
:W:
"""
for k in CK:
if k.input_dim <> input_dim:
k.input_dim = input_dim
#raise Warning("kernel's input dimension overwritten to fit input_dim parameter.")
warnings.warn("kernel's input dimension overwritten to fit input_dim parameter.")
for k in NC:
if k.input_dim <> input_dim + 1:
k.input_dim = input_dim + 1
#raise Warning("kernel's input dimension overwritten to fit input_dim parameter.")
warnings.warn("kernel's input dimension overwritten to fit input_dim parameter.")
kernel = CK[0].prod(kern.coregionalise(Nout,W),tensor=True)
for k in CK[1:]:
kernel += k.prod(kern.coregionalise(Nout,W),tensor=True)
for k in NC:
kernel += k
return kernel