1. 解析路由模型解的内容，生成线路。
- 客户的运输线路和顺序。
routes = []for route_nbr in range(self.routing.vehicles()): index = self.routing.Start(route_nbr) route = [self.manager.IndexToNode(index)] while not self.routing.IsEnd(index): index = solution.Value(self.routing.NextVar(index)) route.append(self.manager.IndexToNode(index)) routes.append(route)
- 客户的到达时间、等待时间
time_dimension = self.routing.GetDimensionOrDie('Time')cumul_datas = []for i in range(self.data["params"]["vehicle_nums"]): cumul_data = [] _times = {} # 返回车辆的开始索引 index = self.routing.Start(i) _times["wait_time"] = 0 _times["arrive_time"] = solution.Min(time_dimension.CumulVar(index)) cumul_data.append(_times) while not self.routing.IsEnd(index): # 返回下一个节点 index = solution.Value(self.routing.NextVar(index)) _times = {} # 下一个节点的等待时间 _times["wait_time"] = solution.Min(time_dimension.SlackVar(index)) if not self.routing.IsEnd(index) else 0 # 下一个节点的到达时间 _times["arrive_time"] = solution.Min(time_dimension.CumulVar(index)) cumul_data.append(_times) cumul_datas.append(cumul_data) - 客户的早晚到时间
for i in range(len(routes)): route = routes[i] for j in range(len(route)): index = route[j] if index == 0: route_times[i][j]["early_hours"] = 0 route_times[i][j]["late_hours"] = 0 else: route_times[i][j]["early_hours"] = max(0, self.data["time_windows"][index][0] - route_times[i][j]["arrive_time"]) route_times[i][j]["late_hours"] = max(0, route_times[i][j]["arrive_time"] - self.data["time_windows"][index][1])
2. 转换为精确求解需要的形式。
ini_solution = {} # 储存初始解vehicle_ids = [] # 储存车辆信息# 字典形式保存初始解_x_value, _t_value, _w_value, _e_value, _l_value = {}, {}, {}, {}, {}for i in range(len(routes)): if len(routes[i]) > 2: vehicle_ids.append(i) route = routes[i] route_times = all_times[i] for j in range(1, len(route)): if j > 0: _x_value[(route[j - 1], route[j], start_vehicle_id)] = 1 _t_value[(route[j - 1], start_vehicle_id)] = route_times[j - 1]["arrive_time"] _w_value[(route[j - 1], start_vehicle_id)] = route_times[j - 1]["wait_time"] _e_value[(route[j - 1], start_vehicle_id)] = route_times[j - 1]["early_hours"] _l_value[(route[j - 1], start_vehicle_id)] = route_times[j - 1]["late_hours"] start_vehicle_id += 1ini_solution.update({"x_values": _x_value, "t_values": _t_value, "w_values": _w_value, "e_values": _e_value, "l_values": _l_value}) 3. 以ortools为例，初始解赋值。
solution = self.initial_solutions if self.solver_name == "cp_sat": variables = self.model._CpModel__model.variables if self.solver_name != "cp_sat": variables = self.model.variables() pattern = re.compile(r'[(](.*?)[)]', re.S) if solution is not None: x_values = solution["x_values"] w_values = solution["w_values"] t_values = solution["t_values"] e_values = solution["e_values"] l_values = solution["l_values"] all_vars = [] all_values = [] for i, field in enumerate(variables): if self.solver_name == "cp_sat": name = field.name if self.solver_name != "cp_sat": name = variables[i].name() if len(re.findall(pattern, name)) > 0: key = tuple([int(i) for i in re.findall(pattern, name)[0].split(",")]) if "x" in name: if x_values.get(key, None): if self.solver_name == "cp_sat": self.model.AddHint(i, x_values.get(key)) if self.solver_name != "cp_sat": all_vars.append(self.model.variable(i)) all_values.append(x_values.get(key)) else: if self.solver_name == "cp_sat": self.model.AddHint(i, 0) if self.solver_name != "cp_sat": all_vars.append(self.model.variable(i)) all_values.append(0) elif "w" in name: if w_values.get(key, None): if self.solver_name == "cp_sat": self.model.AddHint(i, w_values.get(key)) if self.solver_name != "cp_sat": all_vars.append(self.model.variable(i)) all_values.append(w_values.get(key)) elif "t" in name: if t_values.get(key, None): if self.solver_name == "cp_sat": self.model.AddHint(i, t_values.get(key)) if self.solver_name != "cp_sat": all_vars.append(self.model.variable(i)) all_values.append(t_values.get(key)) elif "e" in name: if e_values.get(key, None): if self.solver_name == "cp_sat": self.model.AddHint(i, e_values.get(key)) if self.solver_name != "cp_sat": all_vars.append(self.model.variable(i)) all_values.append(e_values.get(key)) elif "l" in name: if l_values.get(key, None): if self.solver_name == "cp_sat": self.model.AddHint(i, l_values.get(key)) if self.solver_name != "cp_sat": all_vars.append(self.model.variable(i)) all_values.append(l_values.get(key)) else: pass if self.solver_name != "cp_sat": self.model.SetHint(all_vars, all_values)
