Always return np.array not th.Tensor

columbus/observables.py

@@ -337,8 +337,6 @@ class CompositionalObservable(Observable):
 
     def get_observation_space(self):
         num = 0
-        low = 99999
-        high = -99999
         for i, obs in enumerate(self.observables):
             space = obs.get_observation_space()
             num += math.prod(space.shape)
@@ -352,9 +350,11 @@ class CompositionalObservable(Observable):
                           shape=(num,), dtype=np.float32)
 
     def get_observation(self):
-        o = [th.reshape(th.Tensor(obs.get_observation()), (-1,))
+        o = [obs.get_observation().reshape((-1))
              for obs in self.observables]
-        o = th.hstack(o)
+        o = np.hstack(o)
+        import pdb
+        pdb.set_trace()
         return o
 
     def draw(self):