update for torch 0.3

Author: MorvanZhou

tutorial-contents/405_DQN_Reinforcement_learning.py

@@ -4,7 +4,7 @@
 More about Reinforcement learning: https://morvanzhou.github.io/tutorials/machine-learning/reinforcement-learning/
 
 Dependencies:
-torch: 0.2
+torch: 0.3
 gym: 0.8.1
 numpy
 """
@@ -60,7 +60,7 @@ def choose_action(self, x):
         if np.random.uniform() < EPSILON:   # greedy
             actions_value = self.eval_net.forward(x)
             action = torch.max(actions_value, 1)[1].data.numpy()
-            action = action[0, 0] if ENV_A_SHAPE == 0 else action.reshape(ENV_A_SHAPE)  # return the argmax index
+            action = action[0] if ENV_A_SHAPE == 0 else action.reshape(ENV_A_SHAPE)  # return the argmax index
         else:   # random
             action = np.random.randint(0, N_ACTIONS)
             action = action if ENV_A_SHAPE == 0 else action.reshape(ENV_A_SHAPE)