【发布时间】：2021-07-08 08:43:57
【问题描述】：
请帮我解决我的周期性载人车辆路线问题。
在 google-groups 上找到相同的问题 here。
我要建模的内容：
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1 个仓库
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多个客户（假设有 4 个）
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多天（假设 3 天）
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具有每公里价格和特定容量的多种车辆类型
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每个客户都有：交货频率和每次交货的需求
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必须为每个客户分配一个交付模式。每个频率可以有多种交付模式。该模式指示当天是否可以交货。频率为 1 和 3 个工作日：
[[1,0,0],[0,1,0],[0,0,1]]，频率为 2，[[1,1,0],[1,0,1],[1,1,0]]，频率为 3：[1,1,1]这些是可能的模式。
每个客户每次发货的需求都是一样的，每天都有一次发货
因此，我们有一组客户必须由一个仓库交付。多种车辆类型可用于该工作。服务日期很灵活，因为只有频率是固定给客户的，但满足需求的可能性有多种。
到目前为止我做了什么：
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我按工作日复制了每个节点。
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我限制每天的depo节点开始和结束。
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我将车辆乘以天数。
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此外，我把日子当作不同种类的货物来处理。当那天不应该使用车辆时，我确实为车辆分配了零容量。
[[10, 15, 15, 0, 0, 0, 0, 0, 0], [0, 0, 0, 10, 15, 15, 0, 0, 0], [0, 0, 0, 0, 0, 0, 10, 15, 15]]前 3 辆车用于第一天，后 3 辆车用于第二天 最后 3 天是第 3 天。
对于需求矩阵，我使用相同的技巧。在 4 个客户 + 1 个仓库的情况下，需求矩阵可能如下所示
[[0, 3, 0, 5, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 3, 4, 5, 2, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 2]]
第一个列表 (3) 中的第二个条目和第二个列表 (3) 中的第 7 个条目是针对同一客户的，只是在两个不同的日期。节点已复制。
到目前为止效果很好。但这不是我想做的。
我确实每天为每个客户分配需求，但我想通过为每个客户选择的交付模式分配需求。
该模型可以将模式[1,0,1] 分配给频率为2 的一位客户，并将[0,0,1] 的模式分配给另一位客户。这样就可以计划在第 3 天同时满足这两个需求的游览。
我需要帮助来定义一个维度来管理向客户分配模式，从而产生“灵活”的需求矩阵。
感谢您的帮助。
完整代码：
"""Periodic Capacited Vehicles Routing Problem (PCVRP)."""
from ortools.constraint_solver import routing_enums_pb2
from ortools.constraint_solver import pywrapcp
import numpy as np
def dublicate_nodes(base_distance_matrix, num_days):
matrix = []
for i in range(num_days):
day_element = []
for node in range(len(base_distance_matrix)):
node_element = []
for day in range(num_days):
node_element.append(base_distance_matrix[node])
day_element.append(np.concatenate(node_element).tolist())
matrix.extend(day_element)
#print(matrix)
return matrix
def depo_nodes(num_days, num_verhicles, num_nodes):
depo_array = []
for day in range(num_days):
for veh in range(int(num_verhicles/num_days)):
depo_array.append(day*num_nodes)
#print(depo_array)
return depo_array
def veh_types_costs(cost_array, num_per_type, num_days):
cost_array_km = []
for day in range(num_days):
for i in range(len(cost_array)):
for num in range(num_per_type[i]):
cost_array_km.append(cost_array[i])
#print(cost_array_km)
return(cost_array_km)
def veh_capacity_matrix(num_vehicle_per_type, vehicle_capacity_type, num_days):
matrix= []
for index in range(num_days):
matrix_element = []
for day in range(num_days):
for i, num in enumerate(num_vehicle_per_type):
for times in range(num):
if day == index:
matrix_element.append(vehicle_capacity_type[i]);
else:
matrix_element.append(0)
matrix.append(matrix_element)
#print(matrix)
return matrix
def create_data_model():
data = {}
data["num_days"] = 3 #Anzahl Tage
### Definition der Fahrezugtypen
data["num_vehicle_per_type"] = [1, 2] #Anzahl Fahrzeuge pro Typ
data["vehicle_costs_type_per_km"] = [1, 0.01] #Kosten pro km pro Fahrzeugtyp
data["vehicle_costs_type_per_stop"] = [1, 1000] #Kosten pro Stop pro Fahrzeugtyp
data['price_per_km'] = veh_types_costs(data["vehicle_costs_type_per_km"], data["num_vehicle_per_type"], data["num_days"]) #Matrix für price_per_km je Fahrzeug ertsellen
data["price_per_stop"] = veh_types_costs(data["vehicle_costs_type_per_stop"], data["num_vehicle_per_type"], data["num_days"])
data["vehicle_capacity_type"] = [10, 15] # Kapaität pro Fahrzeugtyp
data['vehicle_capacities_matrix'] = veh_capacity_matrix(data["num_vehicle_per_type"], data["vehicle_capacity_type"], data["num_days"]) #Kapazitäten pro Fahrzeugs pro Tag
print('vehicle_capacities_matrix')
print(data['vehicle_capacities_matrix'])
data["num_vehicles_per_day"] = sum(data["num_vehicle_per_type"]) #Gesamtanzahl der Fahrzeuge pro Tag
data['num_vehicles'] = data["num_days"] * data["num_vehicles_per_day"]# Gesamtanzahl der Fahrzeuge in gesamten Zeitraum
###Distanzmatrix bestimmen
data["base_distance_matrix"] = [
[
0, 548, 776, 696, 582
],
[
548, 0, 684, 308, 194
],
[
776, 684, 0, 992, 878
],
[
696, 308, 992, 0, 114
],
[
582, 194, 878, 114, 0
]
] #Distanzmatrix mit allen Kunden einzeln
data['distance_matrix'] = dublicate_nodes(data["base_distance_matrix"], data["num_days"]) # Distanzmatrix mit mehrfachen Nodes pro Kunden, je Tag ein Node
###Start und Ende festlegen
data["num_nodes"] = len(data["base_distance_matrix"]) # Anzahl Kunden
data['starts'] = depo_nodes(data["num_days"], data['num_vehicles'], data["num_nodes"]) #Deponodes (Start) für die einzelnen Fahrzeuge (Tage)
data['ends'] = depo_nodes(data["num_days"], data['num_vehicles'], data["num_nodes"]) #Deponodes (Ende) für die einzelnen Fahrzeuge (Tage)
###Demand pro Kunde
data['demands_matrix'] = [[0, 3, 0, 5, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],[0, 0, 0, 0, 0, 0, 3, 4, 5, 2, 0, 0, 0, 0, 0],[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 2]] #Demandmatrix mit je einer list pro Tag
return data
def print_solution(data, manager, routing, solution):
"""Prints solution on console."""
total_distance = 0
total_load = 0
for vehicle_id in range(data['num_vehicles']):
if vehicle_id % data["num_vehicles_per_day"] == 0:
print(("------Tag {}------").format(int(vehicle_id/data["num_vehicles_per_day"])))
if routing.IsVehicleUsed(assignment= solution, vehicle=vehicle_id) == False:
continue
index = routing.Start(vehicle_id)
if vehicle_id >= data["num_vehicles_per_day"]:
plan_output = 'Route for vehicle {}:\n'.format(abs(vehicle_id-data["num_vehicles_per_day"]*int(vehicle_id/data["num_vehicles_per_day"])))
else:
plan_output = 'Route for vehicle {}:\n'.format(vehicle_id)
route_costs = 0
route_load = 0
while not routing.IsEnd(index):
node_index = manager.IndexToNode(index)
capacity_ID = int(vehicle_id/data["num_vehicles_per_day"])
route_load += data['demands_matrix'][capacity_ID][node_index]
plan_output += ' {0} Load({1}) -> '.format(node_index, route_load)
previous_index = index
index = solution.Value(routing.NextVar(index))
route_costs += routing.GetArcCostForVehicle(
previous_index, index, vehicle_id)
plan_output += ' {0} Load({1})\n'.format(manager.IndexToNode(index),
route_load)
plan_output += 'Costs of the route: {}€\n'.format(route_costs)
plan_output += 'Load of the route: {}\n'.format(route_load)
print(plan_output)
total_distance += route_costs
total_load += route_load
print('Total costs of all routes: {}€'.format(total_distance))
print('Total load of all routes: {}'.format(total_load))
def main():
"""Periodic CVRP problem."""
# Instantiate the data problem.
data = create_data_model()
# Create the routing index manager.
manager = pywrapcp.RoutingIndexManager(len(data['distance_matrix']), data['num_vehicles'], data['starts'],
data['ends'])
# Create Routing Model.
routing = pywrapcp.RoutingModel(manager)
### Kostenfunktion je Fahrzeug festlegen ###
def create_cost_callback(dist_matrix, km_costs, stop_costs):
# Create a callback to calculate distances between cities.
def distance_callback(from_index, to_index):
from_node = manager.IndexToNode(from_index)
to_node = manager.IndexToNode(to_index)
return int(dist_matrix[from_node][to_node]) * (km_costs) + (stop_costs)
return distance_callback
for i in range(data['num_vehicles']):
cost_callback = create_cost_callback(data['distance_matrix'], data["price_per_km"][i],
data["price_per_stop"][i]) # Callbackfunktion erstellen
cost_callback_index = routing.RegisterTransitCallback(cost_callback) # registrieren
routing.SetArcCostEvaluatorOfVehicle(cost_callback_index, i) # Vehicle zuordnen
#Define Capacities for Vehicles for every Day
def create_demand_callback(demand_matrix, demand_index):
# Create a callback to calculate capacity usage.
def demand_callback(from_index):
#Returns the demand of the node.
# Convert from routing variable Index to demands NodeIndex.
from_node = manager.IndexToNode(from_index)
return demand_matrix[demand_index][from_node]
return demand_callback
for i in range(data["num_days"]): #Jedes Fahrzeug hat pro Tag eine andere Kapazität
demand_callback = create_demand_callback(data['demands_matrix'], i)
demand_callback_index = routing.RegisterUnaryTransitCallback(demand_callback)
dimension_name = 'Capacity_day_{}'.format(i)
routing.AddDimensionWithVehicleCapacity(
demand_callback_index,
0, # null capacity slack
data['vehicle_capacities_matrix'][i], # vehicle maximum capacities
True, # start cumul to zero
dimension_name)
# Setting first solution heuristic.
search_parameters = pywrapcp.DefaultRoutingSearchParameters()
search_parameters.first_solution_strategy = (
routing_enums_pb2.FirstSolutionStrategy.AUTOMATIC)
search_parameters.local_search_metaheuristic = (
routing_enums_pb2.LocalSearchMetaheuristic.AUTOMATIC)
search_parameters.time_limit.FromSeconds(1)
# Solve the problem.
solution = routing.SolveWithParameters(search_parameters)
# Print solution on console.
if solution:
print_solution(data, manager, routing, solution)
return solution
if __name__ == '__main__':
solution_array = []
solution = main()
【问题讨论】：
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交叉发帖时请注明。
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好的，我编辑了这个问题。我希望这样没问题。
标签： python or-tools vehicle-routing