swh:1:snp:d2bcff616bbf538fe8ce2a9c384200307730292a
Tip revision: 0c3e151a3442ac8cd0eb85b9674203e75c288184 authored by Artem Artemev on 19 October 2018, 16:42:59 UTC
Resolve merge conflict.
Resolve merge conflict.
Tip revision: 0c3e151
test_features.py
# Copyright 2017 Mark van der Wilk
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import numpy as np
import tensorflow as tf
import gpflow
from gpflow.test_util import GPflowTestCase
class TestInducingPoints(GPflowTestCase):
def test_feature_len(self):
with self.test_context():
N, D = 17, 3
Z = np.random.randn(N, D)
f = gpflow.features.InducingPoints(Z)
self.assertTrue(len(f), N)
with gpflow.params_as_tensors_for(f):
self.assertTrue(len(f), N)
# GPflow does not support re-assignment with different shapes at the moment
def test_inducing_points_equivalence(self):
# Inducing features must be the same as the kernel evaluations
with self.test_context() as session:
Z = np.random.randn(101, 3)
f = gpflow.features.InducingPoints(Z)
kernels = [
gpflow.kernels.RBF(3, 0.46, lengthscales=np.array([0.143, 1.84, 2.0]), ARD=True),
gpflow.kernels.Periodic(3, 0.4, 1.8)
]
for k in kernels:
self.assertTrue(np.allclose(session.run(f.Kuu(k)), k.compute_K_symm(Z)))
class TestMultiScaleInducing(GPflowTestCase):
def prepare(self):
rbf = gpflow.kernels.RBF(2, 1.3441, lengthscales=np.array([0.3414, 1.234]))
Z = np.random.randn(23, 3)
feature_0lengthscale = gpflow.features.Multiscale(Z, np.zeros(Z.shape))
feature_inducingpoint = gpflow.features.InducingPoints(Z)
return rbf, feature_0lengthscale, feature_inducingpoint
def test_equivalence_inducing_points(self):
# Multiscale must be equivalent to inducing points when variance is zero
with self.test_context() as session:
rbf, feature_0lengthscale, feature_inducingpoint = self.prepare()
Xnew = np.random.randn(13, 3)
ms, point = session.run([feature_0lengthscale.Kuf(rbf, Xnew), feature_inducingpoint.Kuf(rbf, Xnew)])
pd = np.max(np.abs(ms - point) / point * 100)
self.assertTrue(pd < 0.1)
ms, point = session.run([feature_0lengthscale.Kuu(rbf), feature_inducingpoint.Kuu(rbf)])
pd = np.max(np.abs(ms - point) / point * 100)
self.assertTrue(pd < 0.1)
class TestFeaturesPsdSchur(GPflowTestCase):
def test_matrix_psd(self):
# Conditional variance must be PSD.
X = np.random.randn(13, 2)
def init_feat(feature):
if feature is gpflow.features.InducingPoints:
return feature(np.random.randn(71, 2))
elif feature is gpflow.features.Multiscale:
return feature(np.random.randn(71, 2), np.random.rand(71, 2))
featkerns = [(gpflow.features.InducingPoints, gpflow.kernels.RBF),
(gpflow.features.InducingPoints, gpflow.kernels.Matern12),
(gpflow.features.Multiscale, gpflow.kernels.RBF)]
for feat_class, kern_class in featkerns:
with self.test_context() as session:
# rbf, feature, feature_0lengthscale, feature_inducingpoint = self.prepare()
kern = kern_class(2, 1.84, lengthscales=[0.143, 1.53])
feature = init_feat(feat_class)
Kuf, Kuu = session.run([feature.Kuf(kern, X), feature.Kuu(kern, jitter=gpflow.settings.jitter)])
Kff = kern.compute_K_symm(X)
Qff = Kuf.T @ np.linalg.solve(Kuu, Kuf)
self.assertTrue(np.all(np.linalg.eig(Kff - Qff)[0] > 0.0))
if __name__ == "__main__":
tf.test.main()