Change _apply_rl_actions in green wave and added tests

examples/rllab/green_wave.py

@@ -61,16 +61,16 @@ def get_non_flow_params(enter_speed, additional_net_params):
 
 
 def run_task(*_):
-    v_enter = 10
-    inner_length = 300
-    long_length = 100
-    short_length = 300
-    n = 3
-    m = 3
-    num_cars_left = 1
-    num_cars_right = 1
-    num_cars_top = 1
-    num_cars_bot = 1
+    v_enter = 20
+    inner_length = 200
+    long_length = 200
+    short_length = 200
+    n = 1
+    m = 1
+    num_cars_left = 10
+    num_cars_right = 10
+    num_cars_top = 10
+    num_cars_bot = 10
     tot_cars = (num_cars_left + num_cars_right) * m \
         + (num_cars_bot + num_cars_top) * n
 
@@ -95,8 +95,8 @@ def run_task(*_):
 
     tl_logic = TrafficLights(baseline=False)
 
-    additional_env_params = {"target_velocity": 50, "num_steps": 500,
-                             "switch_time": 3.0}
+    additional_env_params = {"target_velocity": 20, "num_steps": 500,
+                             "min_yellow_time": 4.0, "min_green_time": 8.0}
     env_params = EnvParams(additional_params=additional_env_params)
 
     additional_net_params = {"speed_limit": 35, "grid_array": grid_array,

flow/envs/green_wave_env.py

@@ -9,8 +9,10 @@
 from flow.envs.base_env import Env
 
 ADDITIONAL_ENV_PARAMS = {
-    # minimum switch time for each traffic light (in seconds)
-    "switch_time": 2.0,
+    # minimum switch time for a traffic light in the yellow phase (in seconds)
+    "min_yellow_time": 2.0,
+    # minimum switch time for a traffic light in the green phase (in seconds)
+    "min_green_time": 8.0,
     # whether the traffic lights should be actuated by sumo or RL
     # options are "controlled" and "actuated"
     "tl_type": "controlled",
@@ -76,11 +78,13 @@ def __init__(self, env_params, sumo_params, scenario):
         # keeps track of the last time the light was allowed to change.
         self.last_change = np.zeros((self.rows * self.cols, 3))
 
-        # when this hits min_switch_time we change from yellow to red
+        # When this hits min_yellow_time we can change from yellow to red.
+        # When this hits min_green_time, we can change from green to yellow.
         # the second column indicates the direction that is currently being
         # allowed to flow. 0 is flowing top to bottom, 1 is left to right
         # For third column, 0 signifies yellow and 1 green or red
-        self.min_switch_time = env_params.additional_params["switch_time"]
+        self.min_yellow_time = env_params.additional_params["min_yellow_time"]
+        self.min_green_time = env_params.additional_params["min_green_time"]
 
         if self.tl_type != "actuated":
             for i in range(self.rows * self.cols):
@@ -156,7 +160,7 @@ def _apply_rl_actions(self, rl_actions):
             # should switch to red
             if self.last_change[i, 2] == 0:  # currently yellow
                 self.last_change[i, 0] += self.sim_step
-                if self.last_change[i, 0] >= self.min_switch_time:
+                if self.last_change[i, 0] >= self.min_yellow_time:
                     if self.last_change[i, 1] == 0:
                         self.traffic_lights.set_state(
                             node_id='center{}'.format(i),
@@ -165,9 +169,11 @@ def _apply_rl_actions(self, rl_actions):
                         self.traffic_lights.set_state(
                             node_id='center{}'.format(i),
                             state='rrrGGGrrrGGG', env=self)
+                    self.last_change[i, 0] = 0.0
                     self.last_change[i, 2] = 1
-            else:
-                if action:
+            else: # currently green
+                self.last_change[i, 0] += self.sim_step
+                if self.last_change[i, 0] >= self.min_green_time and rl_mask[i]:
                     if self.last_change[i, 1] == 0:
                         self.traffic_lights.set_state(
                             node_id='center{}'.format(i),
@@ -179,6 +185,7 @@ def _apply_rl_actions(self, rl_actions):
                     self.last_change[i, 0] = 0.0
                     self.last_change[i, 1] = not self.last_change[i, 1]
                     self.last_change[i, 2] = 0
+
 
     def compute_reward(self, state, rl_actions, **kwargs):
         return rewards.penalize_tl_changes(rl_actions >= 0.5, gain=1.0)

tests/fast_tests/test_traffic_lights.py

@@ -9,6 +9,7 @@
 from flow.core.experiment import SumoExperiment
 from flow.controllers.routing_controllers import GridRouter
 from flow.controllers.car_following_models import IDMController
+from flow.envs.green_wave_env import PO_TrafficLightGridEnv
 
 os.environ["TEST_FLAG"] = "True"
 
@@ -194,6 +195,45 @@ def test_k_closest(self):
             self.assertTrue(self.env.vehicles.get_edge(veh_id) in c0_edges)
 
 
+    def test_min_switch(self):
+        # FOR THE PURPOSES OF THIS TEST, never set min switch to be < 2
+
+        # reset the environment
+        self.env.reset()
+
+        # Set up RL environment
+        self.env = PO_TrafficLightGridEnv(self.env.env_params,
+                                          self.env.sumo_params,
+                                          self.env.scenario)
+
+        for i in range(len(self.env.last_change)):
+            self.assertEqual(self.env.last_change[i, 2], 1)
+
+        # Run one step and make sure the count is incrementing
+        self.env.step([1] * self.env.num_traffic_lights)
+        for i in range(len(self.env.last_change)):
+            self.assertEqual(self.env.last_change[i, 0], 1)
+            self.assertEqual(self.env.last_change[i, 1], 0)
+            self.assertEqual(self.env.last_change[i, 2], 1)
+
+        # Run until green switches to yellow
+        for i in range(int(self.env.min_green_time - 1.)):
+            self.env.step([1] * self.env.num_traffic_lights)
+        for i in range(len(self.env.last_change)):
+            self.assertEqual(self.env.last_change[i, 0], 0)
+            self.assertEqual(self.env.last_change[i, 1], 1)
+            self.assertEqual(self.env.last_change[i, 2], 0)
+
+        # Run until yellow switches to green
+        for i in range(int(self.env.min_yellow_time)):
+            self.env.step([1] * self.env.num_traffic_lights)
+
+        for i in range(len(self.env.last_change)):
+            self.assertEqual(self.env.last_change[i, 0], 0)
+            self.assertEqual(self.env.last_change[i, 1], 1)
+            self.assertEqual(self.env.last_change[i, 2], 1)
+
+
 class TestItRuns(unittest.TestCase):
     """
     Tests the set_state function

tests/setup_scripts.py

@@ -335,7 +335,7 @@ def grid_mxn_exp_setup(row_num=1,
     if env_params is None:
         # set default env_params configuration
         additional_env_params = {"target_velocity": 50, "num_steps": 100,
-                                 "switch_time": 3.0}
+                                 "min_yellow_time": 3.0, "min_green_time": 8.0}
 
         env_params = EnvParams(additional_params=additional_env_params,
                                horizon=100)