Fix gSDE loading issue in test mode (#45)

* Fix gSDE loading issue in test mode

* Forward `reset_noise` method

* Re-add `make_actor`

* Reformat

docs/misc/changelog.rst

@@ -4,7 +4,7 @@ Changelog
 ==========
 
 
-Pre-Release 0.7.0a0 (WIP)
+Pre-Release 0.7.0a1 (WIP)
 ------------------------------
 
 Breaking Changes:
@@ -18,6 +18,7 @@ Bug Fixes:
 ^^^^^^^^^^
 - Fixed ``render()`` method for ``VecEnvs``
 - Fixed ``seed()``` method for ``SubprocVecEnv``
+- Fixed loading on GPU for testing when using gSDE and ``deterministic=False``
 
 Deprecations:
 ^^^^^^^^^^^^^

stable_baselines3/common/base_class.py

@@ -375,6 +375,10 @@ class BaseRLModel(ABC):
             for name in tensors:
                 recursive_setattr(model, name, tensors[name])
 
+        # Sample gSDE exploration matrix, so it uses the right device
+        # see issue #44
+        if model.use_sde:
+            model.policy.reset_noise()
         return model
 
     @staticmethod

stable_baselines3/sac/policies.py

@@ -128,8 +128,8 @@ class Actor(BasePolicy):
 
         :return: (th.Tensor)
         """
-        assert isinstance(self.action_dist, StateDependentNoiseDistribution), \
-            'get_std() is only available when using gSDE'
+        msg = 'get_std() is only available when using gSDE'
+        assert isinstance(self.action_dist, StateDependentNoiseDistribution), msg
         return self.action_dist.get_std(self.log_std)
 
     def reset_noise(self, batch_size: int = 1) -> None:
@@ -138,8 +138,8 @@ class Actor(BasePolicy):
 
         :param batch_size: (int)
         """
-        assert isinstance(self.action_dist, StateDependentNoiseDistribution), \
-            'reset_noise() is only available when using gSDE'
+        msg = 'reset_noise() is only available when using gSDE'
+        assert isinstance(self.action_dist, StateDependentNoiseDistribution), msg
         self.action_dist.sample_weights(self.log_std, batch_size=batch_size)
 
     def get_action_dist_params(self, obs: th.Tensor) -> Tuple[th.Tensor, th.Tensor, Dict[str, th.Tensor]]:
@@ -354,6 +354,14 @@ class SACPolicy(BasePolicy):
         ))
         return data
 
+    def reset_noise(self, batch_size: int = 1) -> None:
+        """
+        Sample new weights for the exploration matrix, when using gSDE.
+
+        :param batch_size: (int)
+        """
+        self.actor.reset_noise(batch_size=batch_size)
+
     def make_actor(self) -> Actor:
         return Actor(**self.actor_kwargs).to(self.device)
 

stable_baselines3/version.txt

@@ -1 +1 @@
-0.7.0a0
+0.7.0a1