update codes

codes/common/wrappers.py

@@ -0,0 +1,29 @@
+import gym
+
+class TimeLimit(gym.Wrapper):
+    def __init__(self, env, max_episode_steps=None):
+        super(TimeLimit, self).__init__(env)
+        self._max_episode_steps = max_episode_steps
+        self._elapsed_steps = 0
+
+    def step(self, ac):
+        observation, reward, done, info = self.env.step(ac)
+        self._elapsed_steps += 1
+        if self._elapsed_steps >= self._max_episode_steps:
+            done = True
+            info['TimeLimit.truncated'] = True
+        return observation, reward, done, info
+
+    def reset(self, **kwargs):
+        self._elapsed_steps = 0
+        return self.env.reset(**kwargs)
+
+class ClipActionsWrapper(gym.Wrapper):
+    def step(self, action):
+        import numpy as np
+        action = np.nan_to_num(action)
+        action = np.clip(action, self.action_space.low, self.action_space.high)
+        return self.env.step(action)
+
+    def reset(self, **kwargs):
+        return self.env.reset(**kwargs)