better comments in the simulator

lib/stormpy/simulator.py

@@ -23,8 +23,8 @@ class Simulator:
 
     def available_actions(self):
         """
-        Returns an iterable over the available actions. The action mode may be used to select how actions are referred to.
-        TODO: Support multiple action modes
+        Returns an iterable over the available actions.
+        The action mode may be used to select how actions are referred to.
 
         :return:
         """
@@ -55,6 +55,7 @@ class Simulator:
 
     def set_observation_mode(self, mode):
         """
+        Select the observation mode, that is, how the states are represented
 
         :param mode: STATE_LEVEL or PROGRAM_LEVEL
         :type mode:
@@ -64,6 +65,12 @@ class Simulator:
         self._observation_mode = mode
 
     def set_action_mode(self, mode):
+        """
+        Select the action mode, that is, how the actions are represented
+
+        :param mode: SimulatorActionMode.INDEX_LEVEL or SimulatorActionMode.GLOBAL_NAMES
+        :return:
+        """
         if not isinstance(mode, SimulatorActionMode):
             raise RuntimeError("Action mode must be a SimulatorActionMode")
         self._action_mode = mode
@@ -96,7 +103,9 @@ class SparseSimulator(Simulator):
         if self._action_mode == SimulatorActionMode.INDEX_LEVEL:
             return range(self.nr_available_actions())
         else:
-            assert self._model.has_choice_labeling(), "Global names require choice labeling"
+            assert self._action_mode == SimulatorActionMode.GLOBAL_NAMES, "Unknown type of simulator action mode"
+            if not self._model.has_choice_labeling():
+                raise RuntimeError("Global names action mode requires model with choice labeling")
             av_actions = []
             current_state = self._engine.get_current_state()
             for action_offset in range(self.nr_available_actions()):
@@ -150,7 +159,6 @@ class SparseSimulator(Simulator):
             check = self._engine.step(action)
             assert check
         elif self._action_mode == SimulatorActionMode.GLOBAL_NAMES:
-            current_state = self._engine.get_current_state()
             action_index = None
             av_actions = self.available_actions()
             for offset, label in enumerate(av_actions):
@@ -158,14 +166,13 @@ class SparseSimulator(Simulator):
                     action_index = offset
                     break
             if action_index is None:
-                raise ValueError("Could not find action: ")
+                raise ValueError(f"Could not find action: {action}")
             check = self._engine.step(action_index)
             assert check
         else:
-            raise ValueError("Unrecognized type of action %s" % action)
+            raise ValueError(f"Unrecognized type of action {action}")
         return self._report_result()
 
-
     def restart(self):
         self._engine.reset_to_initial_state()
         return self._report_result()