66 lines
1.7 KiB
Python
Executable File
66 lines
1.7 KiB
Python
Executable File
#!/usr/bin/env python3
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from collections import namedtuple
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from ortools.constraint_solver import pywrapcp
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VEHICLE_COUNT = 30
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VEHICLE_CAPACITY = 200
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Customer = namedtuple("Customer", ['index', 'demand', 'x', 'y'])
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print('Init')
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customers = list()
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customers.append(Customer(0, 0, 0, 0))
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customers.append(Customer(1, 1, 1.0, 1.0))
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customers.append(Customer(1, 1, 2.0, 2.0))
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customer_count = len(customers)
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manager = pywrapcp.RoutingIndexManager(3, VEHICLE_COUNT, 0)
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routing = pywrapcp.RoutingModel(manager)
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print('Demand Constraint')
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demands = []
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for i in range(0, customer_count):
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demands.append(customers[i][1])
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routing.AddVectorDimension(demands, VEHICLE_CAPACITY, True, "Demand")
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print('Adding Costs')
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def distance_callback(from_index, to_index):
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#static just for the sake of the example
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return 1
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transit_callback_index = routing.RegisterTransitCallback(distance_callback)
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routing.SetArcCostEvaluatorOfAllVehicles(transit_callback_index)
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routing.CloseModel()
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assignment = routing.Solve(None)
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# Inspect solution and extract routes
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routes = []
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for i in range(0, routing.vehicles()):
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route_number = i
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routes.append([])
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node = routing.Start(route_number)
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route = []
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route.append(0)
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if routing.IsVehicleUsed(assignment, i):
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while True:
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node = assignment.Value(routing.NextVar(node))
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if not routing.IsEnd(node):
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route.append(int(node))
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else:
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break
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route.append(0)
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routes[route_number].append(route)
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#This are the routes as list of lists
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routes = [el[0] for el in routes]
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#Now try to read the routes into a new assigment object fails
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assignment2 = routing.ReadAssignmentFromRoutes(routes, True)
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