Update continuous_action_network.py

network/continuous_action_network.py

@@ -158,6 +158,7 @@ class GaussianActorNet(nn.Module, BasicNet):
         return log_density.sum(1)
 
     def entropy(self, std):
+        var = std.pow(2) + 1e-5
         return 0.5 * (2 * var * np.pi * np.e).log().sum(1).mean()
 
 class GaussianCriticNet(nn.Module, BasicNet):