Implemented plot_latents as an external function in util

This commit is contained in:
Andreas 2013-05-22 16:06:35 +01:00
parent e0fe988d81
commit bd1e98f564
3 changed files with 98 additions and 84 deletions

View file

@ -14,6 +14,7 @@ import itertools
from matplotlib.colors import colorConverter from matplotlib.colors import colorConverter
from matplotlib.figure import SubplotParams from matplotlib.figure import SubplotParams
from GPy.inference.optimization import SCG from GPy.inference.optimization import SCG
from GPy.util import plot_latent
class Bayesian_GPLVM(sparse_GP, GPLVM): class Bayesian_GPLVM(sparse_GP, GPLVM):
""" """
@ -178,18 +179,8 @@ class Bayesian_GPLVM(sparse_GP, GPLVM):
self.dbound_dZtheta = sparse_GP._log_likelihood_gradients(self) self.dbound_dZtheta = sparse_GP._log_likelihood_gradients(self)
return np.hstack((self.dbound_dmuS.flatten(), self.dbound_dZtheta)) return np.hstack((self.dbound_dmuS.flatten(), self.dbound_dZtheta))
def plot_latent(self, which_indices=None, *args, **kwargs): def plot_latent(self, *args, **kwargs):
util.plot_latent_indices(self, *args, **kwargs)
if which_indices is None:
try:
input_1, input_2 = np.argsort(self.input_sensitivity())[:2]
except:
raise ValueError, "cannot Atomatically determine which dimensions to plot, please pass 'which_indices'"
else:
input_1, input_2 = which_indices
ax = GPLVM.plot_latent(self, which_indices=[input_1, input_2], *args, **kwargs)
ax.plot(self.Z[:, input_1], self.Z[:, input_2], '^w')
return ax
def do_test_latents(self, Y): def do_test_latents(self, Y):
""" """

View file

@ -11,6 +11,8 @@ from ..util.linalg import pdinv, PCA
from GP import GP from GP import GP
from ..likelihoods import Gaussian from ..likelihoods import Gaussian
from .. import util from .. import util
from GPy.util import plot_latent
class GPLVM(GP): class GPLVM(GP):
""" """
@ -60,75 +62,5 @@ class GPLVM(GP):
mu, var, upper, lower = self.predict(Xnew) mu, var, upper, lower = self.predict(Xnew)
pb.plot(mu[:,0], mu[:,1],'k',linewidth=1.5) pb.plot(mu[:,0], mu[:,1],'k',linewidth=1.5)
def plot_latent(self, labels=None, which_indices=None, resolution=50, ax=None, marker='o', s=40): def plot_latent(self, *args, **kwargs):
""" util.plot_latent.plot_latent(self, *args, **kwargs)
:param labels: a np.array of size self.N containing labels for the points (can be number, strings, etc)
:param resolution: the resolution of the grid on which to evaluate the predictive variance
"""
if ax is None:
ax = pb.gca()
util.plot.Tango.reset()
if labels is None:
labels = np.ones(self.N)
if which_indices is None:
if self.Q==1:
input_1 = 0
input_2 = None
if self.Q==2:
input_1, input_2 = 0,1
else:
try:
input_1, input_2 = np.argsort(self.input_sensitivity())[:2]
except:
raise ValueError, "cannot Atomatically determine which dimensions to plot, please pass 'which_indices'"
else:
input_1, input_2 = which_indices
#first, plot the output variance as a function of the latent space
Xtest, xx,yy,xmin,xmax = util.plot.x_frame2D(self.X[:,[input_1, input_2]],resolution=resolution)
Xtest_full = np.zeros((Xtest.shape[0], self.X.shape[1]))
Xtest_full[:, :2] = Xtest
mu, var, low, up = self.predict(Xtest_full)
var = var[:, :1]
ax.imshow(var.reshape(resolution, resolution).T,
extent=[xmin[0], xmax[0], xmin[1], xmax[1]], cmap=pb.cm.binary,interpolation='bilinear',origin='lower')
# make sure labels are in order of input:
ulabels = []
for lab in labels:
if not lab in ulabels:
ulabels.append(lab)
for i, ul in enumerate(ulabels):
if type(ul) is np.string_:
this_label = ul
elif type(ul) is np.int64:
this_label = 'class %i'%ul
else:
this_label = 'class %i'%i
if len(marker) == len(ulabels):
m = marker[i]
else:
m = marker
index = np.nonzero(labels==ul)[0]
if self.Q==1:
x = self.X[index,input_1]
y = np.zeros(index.size)
else:
x = self.X[index,input_1]
y = self.X[index,input_2]
ax.scatter(x, y, marker=m, s=s, color=util.plot.Tango.nextMedium(), label=this_label)
ax.set_xlabel('latent dimension %i'%input_1)
ax.set_ylabel('latent dimension %i'%input_2)
if not np.all(labels==1.):
ax.legend(loc=0,numpoints=1)
ax.set_xlim(xmin[0],xmax[0])
ax.set_ylim(xmin[1],xmax[1])
ax.grid(b=False) # remove the grid if present, it doesn't look good
ax.set_aspect('auto') # set a nice aspect ratio
return ax

91
GPy/util/plot_latent.py Normal file
View file

@ -0,0 +1,91 @@
import pylab as pb
import numpy as np
from .. import util
def plot_latent(model, labels=None, which_indices=None, resolution=50, ax=None, marker='o', s=40):
"""
:param labels: a np.array of size model.N containing labels for the points (can be number, strings, etc)
:param resolution: the resolution of the grid on which to evaluate the predictive variance
"""
if ax is None:
ax = pb.gca()
util.plot.Tango.reset()
if labels is None:
labels = np.ones(model.N)
if which_indices is None:
if model.Q==1:
input_1 = 0
input_2 = None
if model.Q==2:
input_1, input_2 = 0,1
else:
try:
input_1, input_2 = np.argsort(model.input_sensitivity())[:2]
except:
raise ValueError, "cannot Atomatically determine which dimensions to plot, please pass 'which_indices'"
else:
input_1, input_2 = which_indices
#first, plot the output variance as a function of the latent space
Xtest, xx,yy,xmin,xmax = util.plot.x_frame2D(model.X[:,[input_1, input_2]],resolution=resolution)
Xtest_full = np.zeros((Xtest.shape[0], model.X.shape[1]))
Xtest_full[:, :2] = Xtest
mu, var, low, up = model.predict(Xtest_full)
var = var[:, :1]
ax.imshow(var.reshape(resolution, resolution).T,
extent=[xmin[0], xmax[0], xmin[1], xmax[1]], cmap=pb.cm.binary,interpolation='bilinear',origin='lower')
# make sure labels are in order of input:
ulabels = []
for lab in labels:
if not lab in ulabels:
ulabels.append(lab)
for i, ul in enumerate(ulabels):
if type(ul) is np.string_:
this_label = ul
elif type(ul) is np.int64:
this_label = 'class %i'%ul
else:
this_label = 'class %i'%i
if len(marker) == len(ulabels):
m = marker[i]
else:
m = marker
index = np.nonzero(labels==ul)[0]
if model.Q==1:
x = model.X[index,input_1]
y = np.zeros(index.size)
else:
x = model.X[index,input_1]
y = model.X[index,input_2]
ax.scatter(x, y, marker=m, s=s, color=util.plot.Tango.nextMedium(), label=this_label)
ax.set_xlabel('latent dimension %i'%input_1)
ax.set_ylabel('latent dimension %i'%input_2)
if not np.all(labels==1.):
ax.legend(loc=0,numpoints=1)
ax.set_xlim(xmin[0],xmax[0])
ax.set_ylim(xmin[1],xmax[1])
ax.grid(b=False) # remove the grid if present, it doesn't look good
ax.set_aspect('auto') # set a nice aspect ratio
return ax
def plot_latent_indices(model, which_indices=None, *args, **kwargs):
if which_indices is None:
try:
input_1, input_2 = np.argsort(model.input_sensitivity())[:2]
except:
raise ValueError, "cannot Automatically determine which dimensions to plot, please pass 'which_indices'"
else:
input_1, input_2 = which_indices
ax = plot_latent(model, which_indices=[input_1, input_2], *args, **kwargs)
# TODO: Here test if there are inducing points...
ax.plot(model.Z[:, input_1], model.Z[:, input_2], '^w')
return ax