STT-tensorflow/tensorflow/compiler/tests/matrix_inverse_op_test.py
Benjamin Kramer 14e1000f60 [TF:XLA] Implement MatrixInverse in terms of QR decomposition and triangular solve
This is rather slow, but allows us to avoid falling back to tensorflow. Once we
have LU decomposition we can switch to using that instead of QR. It also
doesn't support complex numbers, our implementation of QR is not ready for
them.

Nevertheless, I think it's a good start and people can avoid relying on
workarounds for tf.linalg.inv, we can optimize later.

PiperOrigin-RevId: 255058725
2019-06-26 00:37:54 -07:00

87 lines
3.1 KiB
Python

# Copyright 2015 The TensorFlow Authors. All Rights Reserved.
#
# 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.
# ==============================================================================
"""Tests for tensorflow.ops.math_ops.matrix_inverse."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import numpy as np
from tensorflow.compiler.tests import xla_test
from tensorflow.python.framework import dtypes
from tensorflow.python.ops import array_ops
from tensorflow.python.ops import linalg_ops
from tensorflow.python.ops import math_ops
from tensorflow.python.platform import googletest
class InverseOpTest(xla_test.XLATestCase):
def _verifyInverse(self, x, np_type):
for adjoint in False, True:
y = x.astype(np_type)
with self.session() as sess:
# Verify that x^{-1} * x == Identity matrix.
p = array_ops.placeholder(dtypes.as_dtype(y.dtype), y.shape, name="x")
with self.test_scope():
inv = linalg_ops.matrix_inverse(p, adjoint=adjoint)
tf_ans = math_ops.matmul(inv, p, adjoint_b=adjoint)
np_ans = np.identity(y.shape[-1])
if x.ndim > 2:
tiling = list(y.shape)
tiling[-2:] = [1, 1]
np_ans = np.tile(np_ans, tiling)
out = sess.run(tf_ans, feed_dict={p: y})
self.assertAllClose(np_ans, out, rtol=1e-3, atol=1e-3)
self.assertShapeEqual(y, tf_ans)
def _verifyInverseReal(self, x):
for np_type in self.float_types & {np.float64, np.float32}:
self._verifyInverse(x, np_type)
def _makeBatch(self, matrix1, matrix2):
matrix_batch = np.concatenate(
[np.expand_dims(matrix1, 0),
np.expand_dims(matrix2, 0)])
matrix_batch = np.tile(matrix_batch, [2, 3, 1, 1])
return matrix_batch
def testNonsymmetric(self):
# 2x2 matrices
matrix1 = np.array([[1., 2.], [3., 4.]])
matrix2 = np.array([[1., 3.], [3., 5.]])
self._verifyInverseReal(matrix1)
self._verifyInverseReal(matrix2)
# A multidimensional batch of 2x2 matrices
self._verifyInverseReal(self._makeBatch(matrix1, matrix2))
def testSymmetricPositiveDefinite(self):
# 2x2 matrices
matrix1 = np.array([[2., 1.], [1., 2.]])
matrix2 = np.array([[3., -1.], [-1., 3.]])
self._verifyInverseReal(matrix1)
self._verifyInverseReal(matrix2)
# A multidimensional batch of 2x2 matrices
self._verifyInverseReal(self._makeBatch(matrix1, matrix2))
def testEmpty(self):
self._verifyInverseReal(np.empty([0, 2, 2]))
self._verifyInverseReal(np.empty([2, 0, 0]))
if __name__ == "__main__":
googletest.main()