64 lines
1.8 KiB
Python
64 lines
1.8 KiB
Python
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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routing = pywrapcp.RoutingModel(3, VEHICLE_COUNT)
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routing.SetDepot(0)
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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 length(customer1, customer2):
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#static just for the sake of the example
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return 1
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routing.SetCost(length)
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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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