1 | /* Copyright 2015 The TensorFlow Authors. All Rights Reserved. |
2 | |
3 | Licensed under the Apache License, Version 2.0 (the "License"); |
4 | you may not use this file except in compliance with the License. |
5 | You may obtain a copy of the License at |
6 | |
7 | http://www.apache.org/licenses/LICENSE-2.0 |
8 | |
9 | Unless required by applicable law or agreed to in writing, software |
10 | distributed under the License is distributed on an "AS IS" BASIS, |
11 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
12 | See the License for the specific language governing permissions and |
13 | limitations under the License. |
14 | ==============================================================================*/ |
15 | |
16 | #ifndef TENSORFLOW_CORE_KERNELS_SOFTSIGN_OP_H_ |
17 | #define TENSORFLOW_CORE_KERNELS_SOFTSIGN_OP_H_ |
18 | // Functor definition for SoftsignOp and SoftsignGradOp, must be compilable by |
19 | // nvcc. |
20 | |
21 | #include "third_party/eigen3/unsupported/Eigen/CXX11/Tensor" |
22 | #include "tensorflow/core/framework/tensor_types.h" |
23 | |
24 | namespace tensorflow { |
25 | namespace functor { |
26 | |
27 | // Functor used by SoftsignOp to do the computations. |
28 | template <typename Device, typename T> |
29 | struct Softsign { |
30 | // Computes Softsign activation. |
31 | // |
32 | // features: any shape. |
33 | // activations: same shape as "features". |
34 | void operator()(const Device& d, typename TTypes<T>::ConstTensor features, |
35 | typename TTypes<T>::Tensor activations) { |
36 | activations.device(d) = |
37 | features / (features.abs() + features.constant(T(1))); |
38 | } |
39 | }; |
40 | |
41 | // Functor used by SoftsignGradOp to do the computations. |
42 | template <typename Device, typename T> |
43 | struct SoftsignGrad { |
44 | // Computes SoftsignGrad backprops. |
45 | // |
46 | // gradients: gradients backpropagated to the Softsign op. |
47 | // features: inputs that were passed to the Softsign op. |
48 | // backprops: gradients to backpropagate to the Softsign inputs. |
49 | void operator()(const Device& d, typename TTypes<T>::ConstTensor gradients, |
50 | typename TTypes<T>::ConstTensor features, |
51 | typename TTypes<T>::Tensor backprops) { |
52 | backprops.device(d) = |
53 | gradients / (features.abs() + features.constant(T(1))).square(); |
54 | } |
55 | }; |
56 | |
57 | } // namespace functor |
58 | } // namespace tensorflow |
59 | |
60 | #endif // TENSORFLOW_CORE_KERNELS_SOFTSIGN_OP_H_ |
61 | |