Corrected reward ranges for environments

gym_minigrid/envs/gotodoor.py

@@ -14,7 +14,7 @@ class GoToDoorEnv(MiniGridEnv):
     ):
         assert size >= 5
         super().__init__(gridSize=size, maxSteps=10*size)
-        self.reward_range = (-1, 1)
+        self.reward_range = (0, 1)
 
     def _genGrid(self, width, height):
         # Create the grid

gym_minigrid/envs/gotoobject.py

@@ -14,7 +14,7 @@ class GoToObjectEnv(MiniGridEnv):
     ):
         self.numObjs = numObjs
         super().__init__(gridSize=size, maxSteps=5*size)
-        self.reward_range = (-1, 1)
+        self.reward_range = (0, 1)
 
     def _genGrid(self, width, height):
         assert width == height

gym_minigrid/envs/lockedroom.py

@@ -38,8 +38,6 @@ class LockedRoom(MiniGridEnv):
             'image': self.observation_space
         })
 
-        self.reward_range = (-1, 1)
-
     def _genGrid(self, width, height):
         # Create the grid
         grid = Grid(width, height)

gym_minigrid/envs/putnear.py

@@ -14,7 +14,7 @@ class PutNearEnv(MiniGridEnv):
     ):
         self.numObjs = numObjs
         super().__init__(gridSize=size, maxSteps=5*size)
-        self.reward_range = (-1, 1)
+        self.reward_range = (0, 1)
 
     def _genGrid(self, width, height):
         # Create a grid surrounded by walls