public void PrintToConsole(
Day day,
RoutingModel routing,
RoutingIndexManager manager,
Assignment solution)
{
Console.WriteLine("Day " + day.DayNum);
if (day.Locations.Count != 0)
{
// Display dropped nodes.
string droppedNodes = "Dropped nodes:";
for (int index = 0; index < routing.Size(); ++index)
{
if (routing.IsStart(index) || routing.IsEnd(index))
{
continue;
}
if (solution.Value(routing.NextVar(index)) == index)
{
droppedNodes += " " + manager.IndexToNode(index);
}
}
Console.WriteLine("{0}", droppedNodes);
// Inspect solution.
for (int i = 0; i < day.Vehicles.Count; i++)
{
Console.WriteLine("Route for Vehicle {0}:", i);
long routeDuration = 0;
var index = routing.Start(i);
while (routing.IsEnd(index) == false)
{
Console.Write("{0} -> ", manager.IndexToNode((int)index));
var previousIndex = index;
index = solution.Value(routing.NextVar(index));
routeDuration += routing.GetArcCostForVehicle(previousIndex, index, 0);
}
Console.WriteLine("{0}", manager.IndexToNode((int)index));
Console.WriteLine("Duration of the route: {0}mins", routeDuration);
}
Console.WriteLine("Minimum duration of the routes: {0}mins", day.MinDur);
Console.WriteLine("Maximum duration of the routes: {0}mins", day.MaxDur);
}
else
{
Console.WriteLine("This day is holiday.");
}
}
private IList <Dropped> GetDroppedLocations(FileInput input, RoutingIndexManager manager, RoutingModel routing, Assignment solution)
{
IDictionary <int, string> locationsNames = input.Locations.ToDictionary(k => k.Id - 1, v => v.Name);
List <Dropped> droppedLocations = new List <Dropped>();
for (int index = 0; index < routing.Size(); ++index)
{
if (routing.IsStart(index) || routing.IsEnd(index))
{
continue;
}
if (solution.Value(routing.NextVar(index)) == index)
{
int node = manager.IndexToNode(index);
droppedLocations.Add(new Dropped {
LocationName = locationsNames[node]
});
}
}
return(droppedLocations);
}
//IntVar x;
//IntVar y;//Reduntant
public void SolveVrpProblem(Day day, ConfigParams cfg, VrpProblem vrpProblem, IDataOutput dataOutput, int[] VCMinMax)
{
this.day = day;
this.cfg = cfg;
//Google Distance Matrix API (Duration matrix)
// Create Routing Index Manager
manager = new RoutingIndexManager(
day.TimeMatrix.GetLength(0),
day.Vehicles.Count,
day.Depot);
// Create Routing Model.
routing = new RoutingModel(manager);
// Create and register a transit callback.
int transitCallbackIndex = routing.RegisterTransitCallback(
(long fromIndex, long toIndex) =>
{
// Convert from routing variable Index to distance matrix NodeIndex.
var fromNode = manager.IndexToNode(fromIndex);
var toNode = manager.IndexToNode(toIndex);
return(day.TimeMatrix[fromNode, toNode]);
}
);
// Define cost of each arc.
routing.SetArcCostEvaluatorOfAllVehicles(transitCallbackIndex);
// Add Distance constraint.
if (day.TimeWindowsActive != true)
{
routing.AddDimension(transitCallbackIndex, 0, 700000,
true, // start cumul to zero
"Distance");
RoutingDimension distanceDimension = routing.GetMutableDimension("Distance");
distanceDimension.SetGlobalSpanCostCoefficient(100);
}
else
{
routing.AddDimension(
transitCallbackIndex, // transit callback
1000, // allow waiting time
600, // vehicle maximum capacities
false, // start cumul to zero
"Time");
TimeWindowInit(day, routing, manager);//Set Time Window Constraints
}
if (day.MaxVisitsActive != 0)
{
int demandCallbackIndex = routing.RegisterUnaryTransitCallback(
(long fromIndex) => {
// Convert from routing variable Index to demand NodeIndex.
var fromNode = manager.IndexToNode(fromIndex);
return(day.Demands[fromNode]);
}
);
routing.AddDimensionWithVehicleCapacity(
demandCallbackIndex, 0, // null capacity slack
day.VehicleCapacities, // vehicle maximum capacities
true, // start cumul to zero
"Capacity");
}
// Allow to drop nodes.
for (int i = 1; i < day.TimeMatrix.GetLength(0); ++i)
{
routing.AddDisjunction(
new long[] { manager.NodeToIndex(i) }, day.Locations.ElementAt(i).Penalty);
}
// Setting first solution heuristic.
RoutingSearchParameters searchParameters =
operations_research_constraint_solver.DefaultRoutingSearchParameters();
searchParameters.FirstSolutionStrategy =
FirstSolutionStrategy.Types.Value.PathMostConstrainedArc;
//metaheuristic
searchParameters.LocalSearchMetaheuristic = LocalSearchMetaheuristic.Types.Value.GuidedLocalSearch;
searchParameters.TimeLimit = new Duration {
Seconds = cfg.SolutionDuration
};
searchParameters.LogSearch = true;
solver = routing.solver();
//TODO
//Some location must be on same route.
//solver.Add(routing.VehicleVar(manager.NodeToIndex(2)) == routing.VehicleVar(manager.NodeToIndex(5)));
//One node takes precedence over the another.
//routing.AddPickupAndDelivery(manager.NodeToIndex(2), manager.NodeToIndex(5));
//Constraint variable
//x = solver.MakeIntVar(day.Vehicles.Count, day.Vehicles.Count, "x");
//Number of vehicle restriction - old version
//solver.Add(x < 7);
//Number of vehicle restriction -new version
//y = solver.MakeIntVar(routing.Vehicles(), routing.Vehicles(), "y");
//solver.Add(y <= VCMinMax[1]);//Reduntant
// Solve the problem.
solution = routing.SolveWithParameters(searchParameters);
day.LocationDropped = false;
// Display dropped nodes.
List <int> droppedNodes = new List <int>();
for (int index = 0; index < routing.Size(); ++index)
{
if (routing.IsStart(index) || routing.IsEnd(index))
{
continue;
}
if (solution.Value(routing.NextVar(index)) == index)
{
droppedNodes.Add(manager.IndexToNode((int)index));
day.LocationDropped = true;
}
}
day.DroppedLocations.Clear();
Console.WriteLine(day.Locations.ElementAt(0).Name);
if (droppedNodes != null)
{
foreach (var item in droppedNodes)
{
Location location = LocationDB.Locations.Where(x => x.Position.strPos_ == day.Addresses[item]).ToList().ElementAt(0);
if (location != null)
{
Console.WriteLine(location.Name);
day.DroppedLocations.Add(location);
}
}
}
List <int> AssignedNodes = new List <int>();
Console.WriteLine(manager.GetNumberOfNodes());
//Inspect Infeasable Nodes
for (int i = 0; i < day.Vehicles.Count; i++)
{
var index = routing.Start(i);
int j = 0;
while (routing.IsEnd(index) == false)
{
j++;
index = solution.Value(routing.NextVar(index));
}
if (j == 1)
{
day.InfeasibleNodes = true;
foreach (var item in day.DroppedLocations)
{
LocationDB.Locations.Where(x => x.ClientRef == item.ClientRef).ToList().ElementAt(0).Infeasible = true;
}
if (day.Vehicles.Count - 1 >= 1)
{
day.SetVehicleNumber(day.Vehicles.Count - 1);
day.ResetResults();
vrpProblem.SolveVrpProblem(day, cfg, vrpProblem, dataOutput, VCMinMax);
}
return;
}
}
// Inspect solution.
day.TotalDur = 0;
day.MinDur = 100000;
for (int i = 0; i < day.Vehicles.Count; i++)
{
long routeDuration = 0;
var index = routing.Start(i);
while (routing.IsEnd(index) == false)
{
var previousIndex = index;
index = solution.Value(routing.NextVar(index));
routeDuration += routing.GetArcCostForVehicle(previousIndex, index, 0);
}
day.TotalDur += routeDuration;
day.MaxDur = Math.Max(routeDuration, day.MaxDur);
day.MinDur = Math.Min(routeDuration, day.MinDur);
}
day.AvgDur = day.TotalDur / day.Vehicles.Count;
}