fix issues

Author: AndreasMadsen

README.md

@@ -12,6 +12,7 @@ developments that cannot be integrated into core TensorFlow
 ## Contents
 | Sub-Package    | Addon  | Reference                                  |
 |:----------------------- |:----------- |:---------------------------- |
+| addons.activations | Sparsemax | https://arxiv.org/abs/1602.02068    |
 | addons.image | transform |                                           |
 | addons.layers | Maxout | https://arxiv.org/abs/1302.4389             |
 | addons.layers | PoinareNormalize | https://arxiv.org/abs/1705.08039  |

tensorflow_addons/activations/README.md

@@ -0,0 +1,27 @@
+# Addons - Layers
+
+## Contents
+| Layer  | Reference                                     |
+|:----------------------- |:-----------------------------|
+| Sparsemax | https://arxiv.org/abs/1602.02068           |
+
+
+## Contribution Guidelines
+#### Standard API
+In order to conform with the current API standard, all activations
+must:
+ * Be a `tf.function`.
+ * Have the signature `fn(input, axis=-1, name=None)`.
+ * [Register as a keras global object](https://github.com/tensorflow/addons/blob/master/tensorflow_addons/utils/python/keras_utils.py)
+  so it can be serialized properly.
+ * Add the addon to the `py_library` in this sub-package's BUILD file.
+
+#### Testing Requirements
+ * Simple unittests that demonstrate the layer is behaving as expected.
+ * When applicable, run all unittests with TensorFlow's
+  `@run_all_in_graph_and_eager_modes` decorator.
+ * Add a `py_test` to this sub-package's BUILD file.
+
+#### Documentation Requirements
+ * Update the table of contents in the project's central README.
+ * Update the table of contents in this sub-package's README.

tensorflow_addons/activations/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2016 The TensorFlow Authors. All Rights Reserved.
+# Copyright 2019 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.

tensorflow_addons/activations/python/sparsemax.py

@@ -21,6 +21,7 @@
 
 from tensorflow_addons.utils.python import keras_utils
 
+@tf.function
 @keras_utils.register_keras_custom_object
 def sparsemax(logits, axis=-1, name=None):
   """Sparsemax activation function [1].

tensorflow_addons/activations/python/sparsemax_test.py

@@ -270,7 +270,8 @@ def test_gradient_against_estimate(self, dtype=None):
 
     (jacob_sym, ), (jacob_num, ) = tf.test.compute_gradient(
       lambda logits: sparsemax(logits),
-      [z])
+      [z],
+      delta=1e-6)
     self.assertAllCloseAccordingToType(jacob_sym, jacob_num)
 
 if __name__ == '__main__':

tensorflow_addons/layers/__init__.py

@@ -20,5 +20,5 @@
 
 from tensorflow_addons.layers.python.maxout import Maxout
 from tensorflow_addons.layers.python.poincare import PoincareNormalize
-from tensorflow_addons.layers.python.wrappers import WeightNormalization
 from tensorflow_addons.layers.python.sparsemax import Sparsemax
+from tensorflow_addons.layers.python.wrappers import WeightNormalization

tensorflow_addons/losses/__init__.py

@@ -18,5 +18,5 @@
 from __future__ import division
 from __future__ import print_function
 
-from tensorflow_addons.losses.python.triplet import triplet_semihard_loss
 from tensorflow_addons.losses.python.sparsemax_loss import sparsemax_loss, SparsemaxLoss
+from tensorflow_addons.losses.python.triplet import triplet_semihard_loss

tensorflow_addons/utils/python/keras_utils.py

@@ -17,8 +17,9 @@
 from __future__ import division
 from __future__ import print_function
 
-from tensorflow.python.keras.utils import generic_utils
+# TODO: find public API alternative to these
 from tensorflow.python.keras.losses import LossFunctionWrapper
+from tensorflow.python.keras.utils import generic_utils
 
 
 def register_keras_custom_object(cls):