/// <summary>
/// Makes a solver named variable ranging over the values <paramref name="vmin"/>,
/// <paramref name="vmax"/>, and the step <paramref name="vstep"/>. Returns the
/// <see cref="IntVar"/> after it has been made.
/// </summary>
/// <param name="solver"></param>
/// <param name="vmin"></param>
/// <param name="vmax"></param>
/// <param name="vstep"></param>
/// <param name="name"></param>
/// <returns></returns>
public static IntVar MakeIntVar(this Solver solver, long vmin, long vmax, long vstep, string name)
{
var values = new CpInt64Vector();
for (var v = vmin; v <= vmax; v += vstep)
values.Add(v);
return solver.MakeIntVar(values, name);
}
/// <summary>
/// Makes a solver named variable ranging over the values <paramref name="vmin"/>,
/// <paramref name="vmax"/>, and the step <paramref name="vstep"/>. Returns the
/// <see cref="IntVar"/> after it has been made.
/// </summary>
/// <param name="solver"></param>
/// <param name="vmin"></param>
/// <param name="vmax"></param>
/// <param name="vstep"></param>
/// <param name="name"></param>
/// <returns></returns>
public static IntVar MakeIntVar(this Solver solver, long vmin, long vmax, long vstep, string name)
{
var values = new CpInt64Vector();
for (var v = vmin; v <= vmax; v += vstep)
{
values.Add(v);
}
return(solver.MakeIntVar(values, name));
}
protected RoutingModel ComposeRoutingModel(out List <int> failedNodes)
{
failedNodes = new List <int>();
int numberOfSites = Data.GetTimeMatrix().GetLength(0);
// Create Routing Model.
// [START routing_model]
RoutingModel routing = new RoutingModel(manager);
// [END routing_model]
// Define cost of each arc.
// [START arc_cost]
int transitCallbackIndex = routing.RegisterTransitCallback(timeCallback);
routing.SetArcCostEvaluatorOfAllVehicles(transitCallbackIndex);
// [END arc_cost]
// Add Distance constraint.
// [START time_constraint]
// Documentation at: https://github.com/google/or-tools/blob/3494afff17d3dc60daf5ebe6ff2ab4cbc7777163/ortools/constraint_solver/routing.h#L383
routing.AddDimension(
transitCallbackIndex, // transit callback
Data.getAllowWaitingTime(), // allow waiting time
Data.getMaximumWorkerCapacity(), // vehicle maximum capacities
false, // start cumul to zero
"Time");
RoutingDimension timeDimension = routing.GetMutableDimension("Time");
// Add time window constraints for each location except depot
// and 'copy' the slack var in the solution object (aka Assignment) to print it
for (int i = 1; i < Data.GetTimeWindows().GetLength(0); ++i)
{
try
{
long index = manager.NodeToIndex(i);
// TODO: To be replaced to allow mulible shifts similar to:
// https://gist.github.com/Muhammad-Altabba/5e52cc1aee98e88f11a01181341f630e#file-vrpsolver-py-L121
timeDimension.CumulVar(index).SetRange(
Data.GetTimeWindows()[i, 0],
Data.GetTimeWindows()[i, 1]);
routing.AddToAssignment(timeDimension.SlackVar(index));
}
catch (System.ApplicationException ex)
{
//Possible cases: The site cannot be visited during the attendance time of the worker.
// Or the starting time is after the end time...
// Most likely a problem in timing for this node..
failedNodes.Add(i);
Console.WriteLine("(Note: " + ex.Message + " to add for node " + i + ". Could be because the site cannot be visited during the attendance time of the workers. Or there is a time inconsistency for this node.)");
}
}
// Add time window constraints for each vehicle start node
// and 'copy' the slack var in the solution object (aka Assignment) to print
// it
for (int i = 0; i < Data.GetVehicleNumber(); ++i)
{
long index = routing.Start(i);
timeDimension.CumulVar(index).SetRange(
Data.GetTimeWindows()[0, 0],
Data.GetTimeWindows()[0, 1]);
routing.AddToAssignment(timeDimension.SlackVar(index));
}
// [END time_constraint]
for (int i = 0; i < numberOfSites; i++)
{
CpInt64Vector v = new CpInt64Vector();
v.Add(manager.NodeToIndex(i));
routing.AddDisjunction(v, Data.GetDemands()[i]);
}
return(routing);
}
