2018-10-02 12:55:58 -07:00

73 lines
2.1 KiB
Python

# Copyright 2016 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.
# ==============================================================================
"""Identity bijector."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from tensorflow.python.framework import constant_op
from tensorflow.python.ops.distributions import bijector
from tensorflow.python.util import deprecation
__all__ = [
"Identity",
]
class Identity(bijector.Bijector):
"""Compute Y = g(X) = X.
Example Use:
```python
# Create the Y=g(X)=X transform which is intended for Tensors with 1 batch
# ndim and 1 event ndim (i.e., vector of vectors).
identity = Identity()
x = [[1., 2],
[3, 4]]
x == identity.forward(x) == identity.inverse(x)
```
"""
@deprecation.deprecated(
"2019-01-01",
"The TensorFlow Distributions library has moved to "
"TensorFlow Probability "
"(https://github.com/tensorflow/probability). You "
"should update all references to use `tfp.distributions` "
"instead of `tf.distributions`.",
warn_once=True)
def __init__(self, validate_args=False, name="identity"):
super(Identity, self).__init__(
forward_min_event_ndims=0,
is_constant_jacobian=True,
validate_args=validate_args,
name=name)
def _forward(self, x):
return x
def _inverse(self, y):
return y
def _inverse_log_det_jacobian(self, y):
return constant_op.constant(0., dtype=y.dtype)
def _forward_log_det_jacobian(self, x):
return constant_op.constant(0., dtype=x.dtype)