This commit is contained in:
Nicolo Fusi 2013-07-08 14:28:54 +01:00
commit d887e1ceda
4 changed files with 98 additions and 11 deletions

View file

@ -116,12 +116,14 @@ class GPBase(Model):
else:
raise NotImplementedError, "Cannot define a frame with more than two input dimensions"
def plot(self, plot_limits=None, which_data='all', which_parts='all', resolution=None, levels=20, samples=0, fignum=None, ax=None):
def plot(self, plot_limits=None, which_data='all', which_parts='all', resolution=None, levels=20, samples=0, fignum=None, ax=None, fixed_inputs=[], linecol=Tango.colorsHex['darkBlue'],fillcol=Tango.colorsHex['lightBlue']):
"""
TODO: Docstrings!
:param levels: for 2D plotting, the number of contour levels to use
is ax is None, create a new figure
fixed_inputs: a list of tuple [(i,v), (i,v)...], specifying that input index i should be set to value v.
"""
# TODO include samples
if which_data == 'all':
@ -131,15 +133,25 @@ class GPBase(Model):
fig = pb.figure(num=fignum)
ax = fig.add_subplot(111)
if self.X.shape[1] == 1:
plotdims = self.input_dim - len(fixed_inputs)
if plotdims == 1:
Xu = self.X * self._Xscale + self._Xoffset # NOTE self.X are the normalized values now
Xnew, xmin, xmax = x_frame1D(Xu, plot_limits=plot_limits)
m, _, lower, upper = self.predict(Xnew, which_parts=which_parts)
fixed_dims = np.array([i for i,v in fixed_inputs])
freedim = np.setdiff1d(np.arange(self.input_dim),fixed_dims)
Xnew, xmin, xmax = x_frame1D(Xu[:,freedim], plot_limits=plot_limits)
Xgrid = np.empty((Xnew.shape[0],self.input_dim))
Xgrid[:,freedim] = Xnew
for i,v in fixed_inputs:
Xgrid[:,i] = v
m, _, lower, upper = self.predict(Xgrid, which_parts=which_parts)
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)
gpplot(Xnew, m[:, d], lower[:, d], upper[:, d], axes=ax, edgecol=linecol, fillcol=fillcol)
ax.plot(Xu[which_data,freedim], self.likelihood.data[which_data, d], '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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@ -83,7 +83,7 @@ def coregionalisation_toy2(optim_iters=100):
Y = np.vstack((Y1,Y2))
k1 = GPy.kern.rbf(1) + GPy.kern.bias(1)
k2 = GPy.kern.Coregionalise(2,1)
k2 = GPy.kern.coregionalise(2,1)
k = k1.prod(k2,tensor=True)
m = GPy.models.GPRegression(X,Y,kernel=k)
m.constrain_fixed('.*rbf_var',1.)
@ -114,7 +114,7 @@ def coregionalisation_toy(optim_iters=100):
Y = np.vstack((Y1,Y2))
k1 = GPy.kern.rbf(1)
k2 = GPy.kern.Coregionalise(2,2)
k2 = GPy.kern.coregionalise(2,2)
k = k1.prod(k2,tensor=True)
m = GPy.models.GPRegression(X,Y,kernel=k)
m.constrain_fixed('.*rbf_var',1.)
@ -149,7 +149,7 @@ def coregionalisation_sparse(optim_iters=100):
Z = np.hstack((np.random.rand(num_inducing,1)*8,np.random.randint(0,2,num_inducing)[:,None]))
k1 = GPy.kern.rbf(1)
k2 = GPy.kern.Coregionalise(2,2)
k2 = GPy.kern.coregionalise(2,2)
k = k1.prod(k2,tensor=True) + GPy.kern.white(2,0.001)
m = GPy.models.SparseGPRegression(X,Y,kernel=k,Z=Z)

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@ -296,5 +296,5 @@ def independent_outputs(k):
"""
for sl in k.input_slices:
assert (sl.start is None) and (sl.stop is None), "cannot adjust input slices! (TODO)"
new_parts = [parts.independent_outputs.IndependentOutputs(p) for p in k.parts]
return kern(k.input_dim+1,new_parts)
_parts = [parts.independent_outputs.IndependentOutputs(p) for p in k.parts]
return kern(k.input_dim+1,_parts)

View file

@ -0,0 +1,75 @@
# Copyright (c) 2012, James Hesnsman
# Licensed under the BSD 3-clause license (see LICENSE.txt)
from kernpart import Kernpart
import numpy as np
from independent_outputs import index_to_slices
class hierarchical(Kernpart):
"""
A kernel part which can reopresent a hierarchy of indepencnce: a gerenalisation of independent_outputs
"""
def __init__(self,parts):
self.levels = len(parts)
self.input_dim = parts[0].input_dim + 1
self.num_params = np.sum([k.num_params for k in parts])
self.name = 'hierarchy'
self.parts = parts
self.param_starts = np.hstack((0,np.cumsum([k.num_params for k in self.parts[:-1]])))
self.param_stops = np.cumsum([k.num_params for k in self.parts])
def _get_params(self):
return np.hstack([k._get_params() for k in self.parts])
def _set_params(self,x):
[k._set_params(x[start:stop]) for start, stop in zip(self.param_starts, self.param_stops)]
def _get_param_names(self):
return self.k._get_param_names()
def _sort_slices(self,X,X2):
slices = [index_to_slices(x) for x in X[-self.levels:].T]
X = X[:-self.levels]
if X2 is None:
slices2 = slices
X2 = X
else:
slices2 = [index_to_slices(x) for x in X2[-self.levels:].T]
X2 = X2[:-self.levels]
return X, X2, slices, slices2
def K(self,X,X2,target):
X, X2, slices, slices2 = self._sort_slices(X,X2)
[[[k.K(X[s],X2[s2],target[s,s2]) for s in slices_i] for s2 in slices_j] for k,slices_i,slices_j in zip(self.parts,slices,slices2)]
def Kdiag(self,X,target):
raise NotImplementedError
#X,slices = X[:,:-1],index_to_slices(X[:,-1])
#[[self.k.Kdiag(X[s],target[s]) for s in slices_i] for slices_i in slices]
def dK_dtheta(self,dL_dK,X,X2,target):
[[[k.dK_dtheta(dL_dK[s,s2],X[s],X2[s2],target[p_start:p_stop]) for s in slices_i] for s2 in slices_j] for k,slices_i,slices_j, p_start, p_stop in zip(self.parts, slices, slices2, self.param_starts, self.param_stops)]
def dK_dX(self,dL_dK,X,X2,target):
raise NotImplementedError
#X,slices = X[:,:-1],index_to_slices(X[:,-1])
#if X2 is None:
#X2,slices2 = X,slices
#else:
#X2,slices2 = X2[:,:-1],index_to_slices(X2[:,-1])
#[[[self.k.dK_dX(dL_dK[s,s2],X[s],X2[s2],target[s,:-1]) for s in slices_i] for s2 in slices_j] for slices_i,slices_j in zip(slices,slices2)]
#
def dKdiag_dX(self,dL_dKdiag,X,target):
raise NotImplementedError
#X,slices = X[:,:-1],index_to_slices(X[:,-1])
#[[self.k.dKdiag_dX(dL_dKdiag[s],X[s],target[s,:-1]) for s in slices_i] for slices_i in slices]
def dKdiag_dtheta(self,dL_dKdiag,X,target):
raise NotImplementedError
#X,slices = X[:,:-1],index_to_slices(X[:,-1])
#[[self.k.dKdiag_dX(dL_dKdiag[s],X[s],target) for s in slices_i] for slices_i in slices]