From 72f92d4dd906ac472ab50c20104e148df988afbe Mon Sep 17 00:00:00 2001
From: nathanlct <nathanlct@icloud.com>
Date: Sun, 28 Jul 2019 04:00:44 -0700
Subject: [PATCH] Fix bug of vehicles colliding

---
 examples/sumo/highway_ramps.py  |  6 ++++--
 flow/scenarios/highway_ramps.py | 30 ------------------------------
 2 files changed, 4 insertions(+), 32 deletions(-)

diff --git a/examples/sumo/highway_ramps.py b/examples/sumo/highway_ramps.py
index e21222f20..76ef21e11 100644
--- a/examples/sumo/highway_ramps.py
+++ b/examples/sumo/highway_ramps.py
@@ -1,7 +1,8 @@
 """Example of a highway section network with on/off ramps."""
 
 from flow.core.params import SumoParams, EnvParams, \
-    NetParams, InitialConfig, InFlows, SumoCarFollowingParams
+    NetParams, InitialConfig, InFlows, SumoCarFollowingParams, \
+    SumoLaneChangeParams
 from flow.core.params import VehicleParams
 from flow.core.experiment import Experiment
 from flow.scenarios.highway_ramps import HighwayRampsScenario, \
@@ -68,7 +69,8 @@ def highway_ramps_example(render=True):
         }),
         car_following_params=SumoCarFollowingParams(
             speed_mode="obey_safe_speed",
-        ))
+        ),
+        lane_change_params=SumoLaneChangeParams(lane_change_mode=1621))
 
     env_params = EnvParams(
         additional_params=ADDITIONAL_ENV_PARAMS,
diff --git a/flow/scenarios/highway_ramps.py b/flow/scenarios/highway_ramps.py
index 22dd37383..f11b98bc5 100644
--- a/flow/scenarios/highway_ramps.py
+++ b/flow/scenarios/highway_ramps.py
@@ -215,36 +215,6 @@ def get_routes(start_node_pos):
 
         return rts
 
-    def specify_connections(self, net_params):
-        """See parent class."""
-        conn_dict = defaultdict(list)
-        for x in self.ramps_pos:
-            highway_id = self.highway_pos[x]
-            ramp_id = self.ramp_pos[x]
-            idx = "highway_{}".format(highway_id)
-            if ramp_id.startswith("on"):
-                for i in range(self.on_ramps_lanes):
-                    conn_dict[idx] += [{"from": ramp_id,
-                                        "to": "highway_{}".format(highway_id),
-                                        "fromLane": str(i),
-                                        "toLane": "0"}]
-            else:
-                for i in range(self.highway_lanes):
-                    for j in range(self.off_ramps_lanes):
-                        conn_dict[idx] += [{"from": "highway_{}".format(
-                                                highway_id - 1),
-                                            "to": ramp_id,
-                                            "fromLane": str(i),
-                                            "toLane": str(j)}]
-            for i in range(self.highway_lanes):
-                conn_dict[idx] += [{"from": "highway_{}".format(
-                                        highway_id - 1),
-                                    "to": "highway_{}".format(highway_id),
-                                    "fromLane": str(i),
-                                    "toLane": str(i)}]
-
-        return conn_dict
-
     def specify_types(self, net_params):
         """See parent class."""
         types = [{