added gaussian noise exploration

krfricke · krfricke · commit 51db4e87339e · 2018-02-19T20:45:35.000+01:00
diff --git a/examples/configs/ddpg.json b/examples/configs/ddpg.json
@@ -32,10 +32,9 @@
     "target_update_weight": 0.999,
 
     "actions_exploration": {
-        "type": "ornstein_uhlenbeck",
+        "type": "gaussian_noise",
         "sigma": 0.2,
-        "mu": 0.0,
-        "theta": 0.15
+        "mu": 0.0
     },
 
     "saver": {
diff --git a/tensorforce/core/explorations/__init__.py b/tensorforce/core/explorations/__init__.py
@@ -18,15 +18,25 @@
 from tensorforce.core.explorations.constant import Constant
 from tensorforce.core.explorations.epsilon_anneal import EpsilonAnneal
 from tensorforce.core.explorations.epsilon_decay import EpsilonDecay
+from tensorforce.core.explorations.gaussian_noise import GaussianNoise
 from tensorforce.core.explorations.ornstein_uhlenbeck_process import OrnsteinUhlenbeckProcess
 
 
 explorations = dict(
     constant=Constant,
     epsilon_anneal=EpsilonAnneal,
     epsilon_decay=EpsilonDecay,
+    gaussian_noise=GaussianNoise,
     ornstein_uhlenbeck=OrnsteinUhlenbeckProcess
 )
 
 
-__all__ = ['Exploration', 'Constant', 'EpsilonAnneal', 'EpsilonDecay', 'OrnsteinUhlenbeckProcess', 'explorations']
+__all__ = [
+    'Exploration',
+    'Constant',
+    'EpsilonAnneal',
+    'EpsilonDecay',
+    'GaussianNoise',
+    'OrnsteinUhlenbeckProcess',
+    'explorations'
+]
diff --git a/tensorforce/core/explorations/gaussian_noise.py b/tensorforce/core/explorations/gaussian_noise.py
@@ -0,0 +1,42 @@
+# Copyright 2017 reinforce.io. 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.
+# ==============================================================================
+
+import tensorflow as tf
+
+from tensorforce.core.explorations import Exploration
+
+
+class GaussianNoise(Exploration):
+    """
+    Explores via gaussian noise.
+    """
+
+    def __init__(
+        self,
+        sigma=0.3,
+        mu=0.0,
+        scope='gaussian_noise',
+        summary_labels=()
+    ):
+        """
+        Initializes distribution values for gaussian noise
+        """
+        self.sigma = sigma
+        self.mu = float(mu)  # need to add cast to float to avoid tf type-mismatch error in case mu=0.0
+
+        super(GaussianNoise, self).__init__(scope=scope, summary_labels=summary_labels)
+
+    def tf_explore(self, episode, timestep, action_shape):
+        return tf.random_normal(shape=action_shape[1:], mean=self.mu, stddev=self.sigma)
