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ortools-clone/examples/notebook/constraint_solver/vrp_pickup_delivery.ipynb
2022-06-27 15:42:26 +02:00

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{
"cells": [
{
"cell_type": "markdown",
"id": "google",
"metadata": {},
"source": [
"##### Copyright 2022 Google LLC."
]
},
{
"cell_type": "markdown",
"id": "apache",
"metadata": {},
"source": [
"Licensed under the Apache License, Version 2.0 (the \"License\");\n",
"you may not use this file except in compliance with the License.\n",
"You may obtain a copy of the License at\n",
"\n",
" http://www.apache.org/licenses/LICENSE-2.0\n",
"\n",
"Unless required by applicable law or agreed to in writing, software\n",
"distributed under the License is distributed on an \"AS IS\" BASIS,\n",
"WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n",
"See the License for the specific language governing permissions and\n",
"limitations under the License.\n"
]
},
{
"cell_type": "markdown",
"id": "basename",
"metadata": {},
"source": [
"# vrp_pickup_delivery"
]
},
{
"cell_type": "markdown",
"id": "link",
"metadata": {},
"source": [
"<table align=\"left\">\n",
"<td>\n",
"<a href=\"https://colab.research.google.com/github/google/or-tools/blob/main/examples/notebook/constraint_solver/vrp_pickup_delivery.ipynb\"><img src=\"https://raw.githubusercontent.com/google/or-tools/main/tools/colab_32px.png\"/>Run in Google Colab</a>\n",
"</td>\n",
"<td>\n",
"<a href=\"https://github.com/google/or-tools/blob/main/ortools/constraint_solver/samples/vrp_pickup_delivery.py\"><img src=\"https://raw.githubusercontent.com/google/or-tools/main/tools/github_32px.png\"/>View source on GitHub</a>\n",
"</td>\n",
"</table>"
]
},
{
"cell_type": "markdown",
"id": "doc",
"metadata": {},
"source": [
"First, you must install [ortools](https://pypi.org/project/ortools/) package in this colab."
]
},
{
"cell_type": "code",
"execution_count": null,
"id": "install",
"metadata": {},
"outputs": [],
"source": [
"!pip install ortools"
]
},
{
"cell_type": "markdown",
"id": "description",
"metadata": {},
"source": [
"\n",
"Simple Pickup Delivery Problem (PDP).\n"
]
},
{
"cell_type": "code",
"execution_count": null,
"id": "code",
"metadata": {},
"outputs": [],
"source": [
"from ortools.constraint_solver import routing_enums_pb2\n",
"from ortools.constraint_solver import pywrapcp\n",
"\n",
"\n",
"def create_data_model():\n",
" \"\"\"Stores the data for the problem.\"\"\"\n",
" data = {}\n",
" data['distance_matrix'] = [\n",
" [\n",
" 0, 548, 776, 696, 582, 274, 502, 194, 308, 194, 536, 502, 388, 354,\n",
" 468, 776, 662\n",
" ],\n",
" [\n",
" 548, 0, 684, 308, 194, 502, 730, 354, 696, 742, 1084, 594, 480, 674,\n",
" 1016, 868, 1210\n",
" ],\n",
" [\n",
" 776, 684, 0, 992, 878, 502, 274, 810, 468, 742, 400, 1278, 1164,\n",
" 1130, 788, 1552, 754\n",
" ],\n",
" [\n",
" 696, 308, 992, 0, 114, 650, 878, 502, 844, 890, 1232, 514, 628, 822,\n",
" 1164, 560, 1358\n",
" ],\n",
" [\n",
" 582, 194, 878, 114, 0, 536, 764, 388, 730, 776, 1118, 400, 514, 708,\n",
" 1050, 674, 1244\n",
" ],\n",
" [\n",
" 274, 502, 502, 650, 536, 0, 228, 308, 194, 240, 582, 776, 662, 628,\n",
" 514, 1050, 708\n",
" ],\n",
" [\n",
" 502, 730, 274, 878, 764, 228, 0, 536, 194, 468, 354, 1004, 890, 856,\n",
" 514, 1278, 480\n",
" ],\n",
" [\n",
" 194, 354, 810, 502, 388, 308, 536, 0, 342, 388, 730, 468, 354, 320,\n",
" 662, 742, 856\n",
" ],\n",
" [\n",
" 308, 696, 468, 844, 730, 194, 194, 342, 0, 274, 388, 810, 696, 662,\n",
" 320, 1084, 514\n",
" ],\n",
" [\n",
" 194, 742, 742, 890, 776, 240, 468, 388, 274, 0, 342, 536, 422, 388,\n",
" 274, 810, 468\n",
" ],\n",
" [\n",
" 536, 1084, 400, 1232, 1118, 582, 354, 730, 388, 342, 0, 878, 764,\n",
" 730, 388, 1152, 354\n",
" ],\n",
" [\n",
" 502, 594, 1278, 514, 400, 776, 1004, 468, 810, 536, 878, 0, 114,\n",
" 308, 650, 274, 844\n",
" ],\n",
" [\n",
" 388, 480, 1164, 628, 514, 662, 890, 354, 696, 422, 764, 114, 0, 194,\n",
" 536, 388, 730\n",
" ],\n",
" [\n",
" 354, 674, 1130, 822, 708, 628, 856, 320, 662, 388, 730, 308, 194, 0,\n",
" 342, 422, 536\n",
" ],\n",
" [\n",
" 468, 1016, 788, 1164, 1050, 514, 514, 662, 320, 274, 388, 650, 536,\n",
" 342, 0, 764, 194\n",
" ],\n",
" [\n",
" 776, 868, 1552, 560, 674, 1050, 1278, 742, 1084, 810, 1152, 274,\n",
" 388, 422, 764, 0, 798\n",
" ],\n",
" [\n",
" 662, 1210, 754, 1358, 1244, 708, 480, 856, 514, 468, 354, 844, 730,\n",
" 536, 194, 798, 0\n",
" ],\n",
" ]\n",
" data['pickups_deliveries'] = [\n",
" [1, 6],\n",
" [2, 10],\n",
" [4, 3],\n",
" [5, 9],\n",
" [7, 8],\n",
" [15, 11],\n",
" [13, 12],\n",
" [16, 14],\n",
" ]\n",
" data['num_vehicles'] = 4\n",
" data['depot'] = 0\n",
" return data\n",
"\n",
"\n",
"def print_solution(data, manager, routing, solution):\n",
" \"\"\"Prints solution on console.\"\"\"\n",
" print(f'Objective: {solution.ObjectiveValue()}')\n",
" total_distance = 0\n",
" for vehicle_id in range(data['num_vehicles']):\n",
" index = routing.Start(vehicle_id)\n",
" plan_output = 'Route for vehicle {}:\\n'.format(vehicle_id)\n",
" route_distance = 0\n",
" while not routing.IsEnd(index):\n",
" plan_output += ' {} -> '.format(manager.IndexToNode(index))\n",
" previous_index = index\n",
" index = solution.Value(routing.NextVar(index))\n",
" route_distance += routing.GetArcCostForVehicle(\n",
" previous_index, index, vehicle_id)\n",
" plan_output += '{}\\n'.format(manager.IndexToNode(index))\n",
" plan_output += 'Distance of the route: {}m\\n'.format(route_distance)\n",
" print(plan_output)\n",
" total_distance += route_distance\n",
" print('Total Distance of all routes: {}m'.format(total_distance))\n",
"\n",
"\n",
"def main():\n",
" \"\"\"Entry point of the program.\"\"\"\n",
" # Instantiate the data problem.\n",
" data = create_data_model()\n",
"\n",
" # Create the routing index manager.\n",
" manager = pywrapcp.RoutingIndexManager(len(data['distance_matrix']),\n",
" data['num_vehicles'], data['depot'])\n",
"\n",
" # Create Routing Model.\n",
" routing = pywrapcp.RoutingModel(manager)\n",
"\n",
"\n",
" # Define cost of each arc.\n",
" def distance_callback(from_index, to_index):\n",
" \"\"\"Returns the manhattan distance between the two nodes.\"\"\"\n",
" # Convert from routing variable Index to distance matrix NodeIndex.\n",
" from_node = manager.IndexToNode(from_index)\n",
" to_node = manager.IndexToNode(to_index)\n",
" return data['distance_matrix'][from_node][to_node]\n",
"\n",
" transit_callback_index = routing.RegisterTransitCallback(distance_callback)\n",
" routing.SetArcCostEvaluatorOfAllVehicles(transit_callback_index)\n",
"\n",
" # Add Distance constraint.\n",
" dimension_name = 'Distance'\n",
" routing.AddDimension(\n",
" transit_callback_index,\n",
" 0, # no slack\n",
" 3000, # vehicle maximum travel distance\n",
" True, # start cumul to zero\n",
" dimension_name)\n",
" distance_dimension = routing.GetDimensionOrDie(dimension_name)\n",
" distance_dimension.SetGlobalSpanCostCoefficient(100)\n",
"\n",
" # Define Transportation Requests.\n",
" for request in data['pickups_deliveries']:\n",
" pickup_index = manager.NodeToIndex(request[0])\n",
" delivery_index = manager.NodeToIndex(request[1])\n",
" routing.AddPickupAndDelivery(pickup_index, delivery_index)\n",
" routing.solver().Add(\n",
" routing.VehicleVar(pickup_index) == routing.VehicleVar(\n",
" delivery_index))\n",
" routing.solver().Add(\n",
" distance_dimension.CumulVar(pickup_index) <=\n",
" distance_dimension.CumulVar(delivery_index))\n",
"\n",
" # Setting first solution heuristic.\n",
" search_parameters = pywrapcp.DefaultRoutingSearchParameters()\n",
" search_parameters.first_solution_strategy = (\n",
" routing_enums_pb2.FirstSolutionStrategy.PARALLEL_CHEAPEST_INSERTION)\n",
"\n",
" # Solve the problem.\n",
" solution = routing.SolveWithParameters(search_parameters)\n",
"\n",
" # Print solution on console.\n",
" if solution:\n",
" print_solution(data, manager, routing, solution)\n",
"\n",
"\n",
"main()\n",
"\n"
]
}
],
"metadata": {},
"nbformat": 4,
"nbformat_minor": 5
}