bug fix in HRL HER memory + some small improvements

rl_coach/coach.py

@@ -118,6 +118,9 @@ def parse_arguments(parser: argparse.ArgumentParser) -> argparse.Namespace:
             args.preset = "{}.py:graph_manager".format(os.path.join(get_base_dir(), 'presets', args.preset))
         else:
             args.preset = "{}".format(args.preset)
+            # if a graph manager variable was not specified, try the default of :graph_manager
+            if len(args.preset.split(":")) == 1:
+                args.preset += ":graph_manager"
 
         # verify that the preset exists
         preset_path = args.preset.split(":")[0]

rl_coach/environments/environment.py

@@ -59,7 +59,7 @@ class SingleLevelSelection(LevelSelection):
         if self.selected_level is None:
             logger.screen.error("No level has been selected. Please select a level using the -lvl command line flag, "
                                 "or change the level in the preset. \nThe available levels are: \n{}"
-                                .format(', '.join(self.levels.keys())), crash=True)
+                                .format(', '.join(sorted(self.levels.keys()))), crash=True)
         if self.selected_level not in self.levels.keys():
             logger.screen.error("The selected level ({}) is not part of the available levels ({})"
                                 .format(self.selected_level, ', '.join(self.levels.keys())), crash=True)

rl_coach/memories/episodic/episodic_hrl_hindsight_experience_replay.py

@@ -29,7 +29,7 @@ class EpisodicHRLHindsightExperienceReplayParameters(EpisodicHindsightExperience
 
     @property
     def path(self):
-        return 'memories.episodic.episodic_hrl_hindsight_experience_replay:EpisodicHRLHindsightExperienceReplay'
+        return 'rl_coach.memories.episodic.episodic_hrl_hindsight_experience_replay:EpisodicHRLHindsightExperienceReplay'
 
 
 class EpisodicHRLHindsightExperienceReplay(EpisodicHindsightExperienceReplay):