use limited vehicle num to initiate path in acs-vei

2 files changed, 10 insertions, 4 deletions

diff --git a/multiple_ant_colony_system.py b/multiple_ant_colony_system.py
index 6dced28..751a441 100644
--- a/multiple_ant_colony_system.py
+++ b/multiple_ant_colony_system.py
@@ -233,7 +233,7 @@ class MultipleAntColonySystem:
         global_best_distance = None
 
         # 使用nearest_neighbor_heuristic算法初始化path 和distance
-        current_path, current_path_distance, _ = new_graph.nearest_neighbor_heuristic()
+        current_path, current_path_distance, _ = new_graph.nearest_neighbor_heuristic(max_vehicle_num=vehicle_num)
 
         # 找出当前path中未访问的结点
         current_index_to_visit = list(range(new_graph.node_num))
@@ -373,7 +373,7 @@ class MultipleAntColonySystem:
             while acs_vehicle_thread.is_alive() and acs_time_thread.is_alive():
 
                 # 如果在指定时间内没有搜索到更好的结果，则退出程序
-                given_time = 5
+                given_time = 10
                 if time.time() - start_time_found_improved_solution > 60 * given_time:
                     stop_event.set()
                     self.print_and_write_in_file(file_to_write, '*' * 50)
diff --git a/vrptw_base.py b/vrptw_base.py
index 52cdafa..30c20de 100644
--- a/vrptw_base.py
+++ b/vrptw_base.py
@@ -96,14 +96,18 @@ class VrptwGraph:
             self.pheromone_mat[current_ind][next_ind] += self.rho/best_path_distance
             current_ind = next_ind
 
-    def nearest_neighbor_heuristic(self):
+    def nearest_neighbor_heuristic(self, max_vehicle_num=None):
         index_to_visit = list(range(1, self.node_num))
         current_index = 0
         current_load = 0
         current_time = 0
         travel_distance = 0
         travel_path = [0]
-        while len(index_to_visit) > 0:
+
+        if max_vehicle_num is None:
+            max_vehicle_num = self.node_num
+
+        while len(index_to_visit) > 0 and max_vehicle_num > 0:
             nearest_next_index = self._cal_nearest_next_index(index_to_visit, current_index, current_load, current_time)
 
             if nearest_next_index is None:
@@ -113,6 +117,8 @@ class VrptwGraph:
                 current_time = 0
                 travel_path.append(0)
                 current_index = 0
+
+                max_vehicle_num -= 1
             else:
                 current_load += self.nodes[nearest_next_index].demand