"""Capacited Vehicles Routing Problem (CVRP).""" # [START import] from __future__ import print_function from ortools.constraint_solver import routing_enums_pb2 from ortools.constraint_solver import pywrapcp from utils import * import numpy as np # [END import] # [START data_model] def create_data_model(): """Stores the data for the problem.""" data = {} data['distance_matrix'] = [ [ 0, 548, 776, 696, 582, 274, 502, 194, 308, 194, 536, 502, 388, 354, 468, 776, 662 ], [ 548, 0, 684, 308, 194, 502, 730, 354, 696, 742, 1084, 594, 480, 674, 1016, 868, 1210 ], [ 776, 684, 0, 992, 878, 502, 274, 810, 468, 742, 400, 1278, 1164, 1130, 788, 1552, 754 ], [ 696, 308, 992, 0, 114, 650, 878, 502, 844, 890, 1232, 514, 628, 822, 1164, 560, 1358 ], [ 582, 194, 878, 114, 0, 536, 764, 388, 730, 776, 1118, 400, 514, 708, 1050, 674, 1244 ], [ 274, 502, 502, 650, 536, 0, 228, 308, 194, 240, 582, 776, 662, 628, 514, 1050, 708 ], [ 502, 730, 274, 878, 764, 228, 0, 536, 194, 468, 354, 1004, 890, 856, 514, 1278, 480 ], [ 194, 354, 810, 502, 388, 308, 536, 0, 342, 388, 730, 468, 354, 320, 662, 742, 856 ], [ 308, 696, 468, 844, 730, 194, 194, 342, 0, 274, 388, 810, 696, 662, 320, 1084, 514 ], [ 194, 742, 742, 890, 776, 240, 468, 388, 274, 0, 342, 536, 422, 388, 274, 810, 468 ], [ 536, 1084, 400, 1232, 1118, 582, 354, 730, 388, 342, 0, 878, 764, 730, 388, 1152, 354 ], [ 502, 594, 1278, 514, 400, 776, 1004, 468, 810, 536, 878, 0, 114, 308, 650, 274, 844 ], [ 388, 480, 1164, 628, 514, 662, 890, 354, 696, 422, 764, 114, 0, 194, 536, 388, 730 ], [ 354, 674, 1130, 822, 708, 628, 856, 320, 662, 388, 730, 308, 194, 0, 342, 422, 536 ], [ 468, 1016, 788, 1164, 1050, 514, 514, 662, 320, 274, 388, 650, 536, 342, 0, 764, 194 ], [ 776, 868, 1552, 560, 674, 1050, 1278, 742, 1084, 810, 1152, 274, 388, 422, 764, 0, 798 ], [ 662, 1210, 754, 1358, 1244, 708, 480, 856, 514, 468, 354, 844, 730, 536, 194, 798, 0 ], ] # [START demands_capacities] data['demands'] = [0, 1, 1, 2, 4, 2, 4, 8, 8, 1, 2, 1, 2, 4, 4, 8, 8] data['vehicle_capacities'] = [15, 15, 15, 15] # [END demands_capacities] data['num_vehicles'] = 4 data['depot'] = 0 return data # [END data_model] # [START solution_printer] 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']): index = routing.Start(vehicle_id) plan_output = 'Route for vehicle {}:\n'.format(vehicle_id) route_distance = 0 route_load = 0 while not routing.IsEnd(index): node_index = manager.IndexToNode(index) route_load += data['demands'][node_index] plan_output += ' {0} Load({1}) -> '.format(node_index, route_load) previous_index = index index = solution.Value(routing.NextVar(index)) route_distance += routing.GetArcCostForVehicle( previous_index, index, vehicle_id) plan_output += ' {0} Load({1})\n'.format(manager.IndexToNode(index), route_load) plan_output += 'Distance of the route: {}m\n'.format(route_distance) plan_output += 'Load of the route: {}\n'.format(route_load) print(plan_output) total_distance += route_distance total_load += route_load print('Total distance of all routes: {} m'.format(total_distance)) log_metric('total_distance',total_distance) save('/tmp/main.py') #or some other output print('Total load of all routes: {}'.format(total_load)) # [END solution_printer] def main(): """Solve the CVRP problem.""" # Instantiate the data problem. # [START data] data = create_data_model() # [END data] # Create the routing index manager. # [START index_manager] manager = pywrapcp.RoutingIndexManager(len(data['distance_matrix']), data['num_vehicles'], data['depot']) # [END index_manager] # Create Routing Model. # [START routing_model] routing = pywrapcp.RoutingModel(manager) # [END routing_model] # Create and register a transit callback. # [START transit_callback] def distance_callback(from_index, to_index): """Returns the distance between the two nodes.""" # Convert from routing variable Index to distance matrix NodeIndex. from_node = manager.IndexToNode(from_index) to_node = manager.IndexToNode(to_index) return data['distance_matrix'][from_node][to_node] transit_callback_index = routing.RegisterTransitCallback(distance_callback) # [END transit_callback] # Define cost of each arc. # [START arc_cost] routing.SetArcCostEvaluatorOfAllVehicles(transit_callback_index) # [END arc_cost] # Add Capacity constraint. # [START capacity_constraint] 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 data['demands'][from_node] demand_callback_index = routing.RegisterUnaryTransitCallback( demand_callback) routing.AddDimensionWithVehicleCapacity( demand_callback_index, 0, # null capacity slack data['vehicle_capacities'], # vehicle maximum capacities True, # start cumul to zero 'Capacity') # [END capacity_constraint] # Setting first solution heuristic. # [START parameters] search_parameters = pywrapcp.DefaultRoutingSearchParameters() search_parameters.first_solution_strategy = ( routing_enums_pb2.FirstSolutionStrategy.PATH_CHEAPEST_ARC) # [END parameters] # Solve the problem. # [START solve] solution = routing.SolveWithParameters(search_parameters) # [END solve] # Print solution on console. # [START print_solution] print('printing solutions') if solution: print_solution(data, manager, routing, solution) # [END print_solution] main()