/// <summary>
/// Builds the result route in segments divided by routes between customers.
/// </summary>
/// <returns></returns>
public static List <Result <Route> > TryBuildRoutes <T>(this IDirectedWeightMatrixAlgorithm <T> algorithm, Tour tour)
{
var routes = new List <Result <Route> >();
// TODO: check what to do here, use the cached version or not?
var weightHandler = algorithm.Profile.DefaultWeightHandler(algorithm.Router);
foreach (var pair in tour.Pairs())
{
// TODO: extract more info at once!
var pairFromDepartureId = algorithm.SourcePaths[DirectedHelper.ExtractDepartureId(pair.From)];
var pairToArrivalId = algorithm.TargetPaths[DirectedHelper.ExtractArrivalId(pair.To)];
var pairFromEdgeId = algorithm.Router.Db.Network.GetEdges(pairFromDepartureId.From.Vertex).First(x => x.To == pairFromDepartureId.Vertex).IdDirected();
var pairToEdgeId = algorithm.Router.Db.Network.GetEdges(pairToArrivalId.Vertex).First(x => x.To == pairToArrivalId.From.Vertex).IdDirected();
var pairFromId = DirectedHelper.ExtractId(pair.From);
var pairToId = DirectedHelper.ExtractId(pair.To);
var fromRouterPoint = algorithm.RouterPoints[pairFromId];
var toRouterPoint = algorithm.RouterPoints[pairToId];
var localRouteRaw = algorithm.Router.TryCalculateRaw(algorithm.Profile, weightHandler, pairFromEdgeId, pairToEdgeId, null).Value;
localRouteRaw.StripSource();
localRouteRaw.StripTarget();
var localRoute = algorithm.Router.BuildRoute(algorithm.Profile, weightHandler, fromRouterPoint, toRouterPoint, localRouteRaw);
routes.Add(localRoute);
}
return(routes);
}
/// <summary>
/// Tries all 3Opt Moves for the neighbourhood of v1.
/// </summary>
/// <returns></returns>
public bool Try3OptMoves(TSProblem problem, float[][] weights, Tour tour, int v1, out float delta)
{
// get v_2.
var v2 = tour.GetNeigbour(v1);
if (v2 < 0)
{
delta = 0;
return(false);
}
var betweenV2V1 = tour.Between(v2, v1);
//var weightV1V2 = weights[v1][v2];
var weightV1V2 = weights.WeightWithoutTurns(v1, v2);
if (DirectedHelper.ExtractId(v2) == problem.First && !problem.Last.HasValue)
{ // set to zero if not closed.
weightV1V2 = 0;
}
int v3 = -1;
NearestNeighbours neighbours = null;
if (_nearestNeighbours)
{
neighbours = problem.GetNNearestNeighboursForward(10, DirectedHelper.ExtractId(v1));
}
foreach (int v4 in betweenV2V1)
{
if (v3 >= 0 && v3 != v1)
{
var v4Id = DirectedHelper.ExtractId(v4);
if (!_nearestNeighbours ||
neighbours.Contains(v4Id))
{
//var weightV1V4 = weights[v1][v4];
var weightV1V4 = weights.WeightWithoutTurns(v1, v4);
//var weightV3V4 = weights[v3][v4];
var weightV3V4 = weights.WeightWithoutTurns(v3, v4);
if (v4Id == problem.First && !problem.Last.HasValue)
{ // set to zero if not closed.
weightV1V4 = 0;
weightV3V4 = 0;
}
var weightV1V2PlusV3V4 = weightV1V2 + weightV3V4;
//var weightsV3 = weights[v3];
var weightsV3 = weights[DirectedHelper.ExtractDepartureId(v3)];
if (this.Try3OptMoves(problem, weights, tour, v1, v2, v3, weightsV3, v4, weightV1V2PlusV3V4, weightV1V4, out delta))
{
return(true);
}
}
}
v3 = v4;
}
delta = 0;
return(false);
}
/// <summary>
/// Builds the result route in segments divided by routes between customers.
/// </summary>
/// <returns></returns>
public static List <Route> BuildRoutes <T>(this IDirectedWeightMatrixAlgorithm <T> algorithm, Tour tour)
{
var routes = new List <Route>();
// TODO: check what to do here, use the cached version or not?
var weightHandler = algorithm.Profile.DefaultWeightHandler(algorithm.Router);
foreach (var pair in tour.Pairs())
{
// TODO: extract more info at once!
var pairFromDepartureId = algorithm.SourcePaths[DirectedHelper.ExtractDepartureId(pair.From)];
var pairToArrivalId = algorithm.TargetPaths[DirectedHelper.ExtractArrivalId(pair.To)];
var pairFromEdgeId = algorithm.Router.Db.Network.GetEdges(pairFromDepartureId.From.Vertex).First(x => x.To == pairFromDepartureId.Vertex).IdDirected();
var pairToEdgeId = algorithm.Router.Db.Network.GetEdges(pairToArrivalId.Vertex).First(x => x.To == pairToArrivalId.From.Vertex).IdDirected();
var pairFromId = DirectedHelper.ExtractId(pair.From);
var pairToId = DirectedHelper.ExtractId(pair.To);
var fromRouterPoint = algorithm.RouterPoints[pairFromId];
var toRouterPoint = algorithm.RouterPoints[pairToId];
var localRouteRaw = algorithm.Router.TryCalculateRaw(algorithm.Profile, weightHandler, pairFromEdgeId, pairToEdgeId, null).Value;
localRouteRaw.StripSource();
localRouteRaw.StripTarget();
var localRoute = algorithm.Router.BuildRoute(algorithm.Profile, weightHandler, fromRouterPoint, toRouterPoint, localRouteRaw);
if (localRoute.IsError)
{
throw new Itinero.Exceptions.RouteNotFoundException(
string.Format("Part of the tour was not found: {0}[{1}] -> {2}[{3}] - {4}.",
pair.From, pairFromId, pair.To, pairToId, localRoute.ErrorMessage));
}
routes.Add(localRoute.Value);
}
return(routes);
}
/// <summary>
/// Applies this operator.
/// </summary>
public bool Apply(SequenceDirectedProblem problem, SequenceDirectedObjective objective, Tour solution, out float delta)
{
var weights = problem.Weights;
delta = objective.Zero;
var fitnessBefore = objective.Calculate(problem, solution);
var enumerator = solution.GetEnumerator();
while (enumerator.MoveNext())
{
var previous = enumerator.Current;
var previousDepartureId = DirectedHelper.ExtractDepartureId(previous);
var current = solution.GetNeigbour(previous);
if (current == Constants.NOT_SET)
{ // last of open.
continue;
}
var next = solution.GetNeigbour(current);
var nextArrivalId = Constants.NOT_SET;
if (next != Constants.NOT_SET)
{
nextArrivalId = DirectedHelper.ExtractArrivalId(next);
}
int currentTurn, currentId, currentArrivalId, currentDepartureId;
DirectedHelper.ExtractAll(current, out currentArrivalId, out currentDepartureId, out currentId, out currentTurn);
var weightBefore = weights[previousDepartureId][currentArrivalId];
var weightAfter = float.MaxValue;
var newDirectedId = Constants.NOT_SET;
if (next == Constants.NOT_SET)
{ // there is no next, only one option here:
// 0 or 1: arrival id offset = 0 OR
// 2 or 3: arrival id offset = 1
if (currentArrivalId % 2 == 0)
{ // check turn = 2.
weightAfter = weights[previousDepartureId][currentArrivalId + 1];
if (weightAfter < weightBefore)
{ // do the switch.
newDirectedId = DirectedHelper.BuildDirectedId(currentId, 2);
}
}
else
{ // check turn = 0
weightAfter = weights[previousDepartureId][currentArrivalId - 1];
if (weightAfter < weightBefore)
{ // do the switch.
newDirectedId = DirectedHelper.BuildDirectedId(currentId, 0);
}
}
}
else
{ // three options left, excluding the current one of 4.
weightBefore += weights[currentDepartureId][nextArrivalId];
weightBefore += problem.TurnPenalties[currentTurn];
currentArrivalId = currentArrivalId - (currentArrivalId % 2);
currentDepartureId = currentDepartureId - (currentDepartureId % 2);
for (var i = 0; i < 4; i++)
{
if (i == currentTurn)
{
continue;
}
int arrivalOffset, departureOffset;
DirectedHelper.ExtractOffset(i, out arrivalOffset, out departureOffset);
var newWeightAfter = weights[previousDepartureId][currentArrivalId + arrivalOffset]
+ weights[currentDepartureId + departureOffset][nextArrivalId]
+ problem.TurnPenalties[i];
if (newWeightAfter < weightAfter &&
newWeightAfter < weightBefore)
{
newDirectedId = DirectedHelper.BuildDirectedId(currentId, i);
weightAfter = newWeightAfter;
}
}
}
// switch if a new directed if was found.
if (newDirectedId != Constants.NOT_SET)
{
solution.Replace(current, newDirectedId);
}
}
var fitnessAfter = objective.Calculate(problem, solution);
delta = objective.Subtract(problem, fitnessBefore, fitnessAfter);
return(objective.CompareTo(problem, delta, objective.Zero) > 0);
}
/// <summary>
/// Optimizes the given part of the tour by choosing the best improvements in either the departureOffset or arrivalOffset of the first/last customers or the turns at any of the intermediate ones.
/// </summary>
private float OptimizePart(TSPTWProblem problem, List <int> part)
{
int turn1, arrivalId1, departureId1, id1;
int turn2, arrivalId2, departureId2, id2;
int turn3, arrivalId3, departureId3, id3;
var delta = 0f; // the positive difference.
var arrivalIdChange = -1;
var departureIdChange = -1;
var customerIdx = -1;
var customerTurn = -1;
// try changing the departureId.
DirectedHelper.ExtractAll(part[0], out arrivalId1, out departureId1, out id1, out turn1);
DirectedHelper.ExtractAll(part[1], out arrivalId2, out departureId2, out id2, out turn2);
var weight = problem.TurnPenalties[turn1];
weight += problem.Times[departureId1][arrivalId2];
var new0 = DirectedHelper.SwitchDepartureOffset(part[0]);
DirectedHelper.ExtractAll(new0, out arrivalId3, out departureId3, out id3, out turn3);
var newWeight = problem.TurnPenalties[turn3];
newWeight += problem.Times[departureId3][arrivalId2];
if (newWeight < weight)
{ // there was an improvement found in changing the departure id.
departureIdChange = DirectedHelper.ExtractDepartureId(new0);
delta = newWeight - weight;
}
// try changing the arrivalId.
DirectedHelper.ExtractAll(part[part.Count - 2], out arrivalId1, out departureId1, out id1, out turn1);
DirectedHelper.ExtractAll(part[part.Count - 1], out arrivalId2, out departureId2, out id2, out turn2);
weight = problem.TurnPenalties[turn2];
weight += problem.Times[departureId1][arrivalId2];
var newLast = DirectedHelper.SwitchArrivalOffset(part[part.Count - 1]);
DirectedHelper.ExtractAll(newLast, out arrivalId3, out departureId3, out id3, out turn3);
newWeight = problem.TurnPenalties[turn3];
newWeight += problem.Times[departureId1][arrivalId3];
if (newWeight < weight &&
delta < (newWeight - weight))
{ // there was an improvement found in changing the arrival id.
arrivalIdChange = DirectedHelper.ExtractDepartureId(newLast);
departureIdChange = -1;
delta = newWeight - weight;
}
for (var c = 1; c < part.Count - 1; c++)
{
var perviousDepartureId = DirectedHelper.ExtractDepartureId(part[c - 1]);
DirectedHelper.ExtractAll(part[c], out arrivalId1, out departureId1, out id1, out turn1);
var nextArrivalid = DirectedHelper.ExtractArrivalId(part[c + 1]);
weight = problem.Times[perviousDepartureId][arrivalId1];
weight += problem.TurnPenalties[turn1];
weight += problem.Times[departureId1][nextArrivalid];
for (var t = 0; t < 3; t++)
{
if (t == turn1)
{
continue;
}
var newDirectedId = DirectedHelper.BuildDirectedId(id1, t);
DirectedHelper.ExtractAll(newDirectedId, out arrivalId2, out departureId2, out id2, out turn2);
newWeight = problem.Times[perviousDepartureId][arrivalId2];
newWeight += problem.TurnPenalties[turn2];
newWeight += problem.Times[departureId2][nextArrivalid];
if (newWeight < weight &&
delta < (newWeight - weight))
{ // there was an improvement found in changing the turn.
arrivalIdChange = -1;
departureIdChange = -1;
customerIdx = c;
customerTurn = t;
delta = newWeight - weight;
}
}
}
if (delta > 0)
{
if (departureIdChange != -1)
{
part[0] = DirectedHelper.SwitchDepartureOffset(part[0]);
}
else if (arrivalIdChange != -1)
{
part[part.Count - 1] = DirectedHelper.SwitchArrivalOffset(part[part.Count - 1]);
}
else if (customerIdx != -1)
{
part[customerIdx] = DirectedHelper.BuildDirectedId(
DirectedHelper.ExtractId(part[customerIdx]), customerTurn);
}
}
return(delta);
}
/// <summary>
/// Inserts the given customer at the best location if possible.
/// </summary>
/// <param name="tour">The tour to insert into.</param>
/// <param name="weights">The directed weights.</param>
/// <param name="turnPenalties">The turn pentalties.</param>
/// <param name="customer">The customer to insert.</param>
/// <param name="metric">The metric to use, time, distance or custom.</param>
/// <param name="max">The maximum allowed cost of the insertion.</param>
public static Weight InsertCheapestDirected(this Tour tour, Weight[][] weights, Weight[] turnPenalties, ProfileMetric metric, int customer, Weight max)
{
if (tour.Count == 1)
{ // there is only one customer, the first one in the route.
if (tour.First == tour.Last)
{ // there is one customer but it's both the start and the end.
var firstId = DirectedHelper.ExtractId(tour.First);
var bestCost = new Weight()
{
Distance = float.MaxValue,
Time = float.MaxValue,
Value = float.MaxValue
};
var bestDirected1Id = int.MaxValue;
var bestDirected2Id = int.MaxValue;
for (var turn1 = 0; turn1 < 4; turn1++)
{
var firstDirectedId = DirectedHelper.BuildDirectedId(firstId, turn1);
var firstArrivalId = DirectedHelper.ExtractArrivalId(firstDirectedId);
var firstDepartureId = DirectedHelper.ExtractDepartureId(firstDirectedId);
for (var turn2 = 0; turn2 < 4; turn2++)
{
var customerDirectedId = DirectedHelper.BuildDirectedId(customer, turn2);
var customerArrivalId = DirectedHelper.ExtractArrivalId(customerDirectedId);
var customerDepartureId = DirectedHelper.ExtractDepartureId(customerDirectedId);
var weight = turnPenalties[turn1];
weight += turnPenalties[turn2];
weight += weights[firstDepartureId][customerArrivalId];
weight += weights[customerDepartureId][firstArrivalId];
if (bestCost.GetForMetric(metric) > weight.GetForMetric(metric))
{
bestDirected1Id = firstDirectedId;
bestDirected2Id = customerDirectedId;
bestCost = weight;
}
}
}
if (bestCost.GetForMetric(metric) <= max.GetForMetric(metric))
{
tour.Replace(tour.First, bestDirected1Id);
tour.InsertAfter(tour.First, bestDirected2Id);
return bestCost;
}
}
else
{ // there is one customer, the last one is not set.
var firstId = DirectedHelper.ExtractId(tour.First);
int departureOffset1, arrivalOffset2;
var cost = DirectedHelper.CheapestInsert(weights, turnPenalties,
firstId, customer, metric, out departureOffset1, out arrivalOffset2);
if (cost.GetForMetric(metric) <= max.GetForMetric(metric))
{
var newFirst = DirectedHelper.UpdateDepartureOffset(
DirectedHelper.BuildDirectedId(firstId, 0), departureOffset1);
var customerDirectedId = DirectedHelper.UpdateArrivalOffset(
DirectedHelper.BuildDirectedId(customer, 0), arrivalOffset2);
tour.Replace(tour.First, newFirst);
tour.InsertAfter(tour.First, customerDirectedId);
return cost;
}
}
}
else
{ // at least 2 customers already exist, insert a new one in between.
var cost = Weight.MaxValue;
var departureOffsetFrom = Constants.NOT_SET;
var arrivalOffsetTo = Constants.NOT_SET;
var turn = Constants.NOT_SET;
var location = new Pair(int.MaxValue, int.MaxValue);
foreach (var pair in tour.Pairs())
{
int departureOffset1, arrivalOffset3, turn2;
var fromIsFirst = tour.IsFirst(pair.From);
var toIsLast = tour.IsLast(pair.To);
var localCost = CheapestInsertionDirectedHelper.CalculateCheapestInsert(weights, turnPenalties, metric, pair.From, customer, pair.To,
!fromIsFirst, !toIsLast, out departureOffset1, out arrivalOffset3, out turn2);
if (localCost.GetForMetric(metric) < cost.GetForMetric(metric))
{
cost = localCost;
location = pair;
departureOffsetFrom = departureOffset1;
arrivalOffsetTo = arrivalOffset3;
turn = turn2;
}
}
if (cost.GetForMetric(metric) <= max.GetForMetric(metric))
{
var directedId = DirectedHelper.BuildDirectedId(customer, turn);
tour.InsertAfter(location.From, directedId);
// update departure offset at from.
var newFromId = DirectedHelper.UpdateDepartureOffset(location.From, departureOffsetFrom);
if (location.From != newFromId)
{
tour.Replace(location.From, newFromId);
}
var newToId = DirectedHelper.UpdateArrivalOffset(location.To, arrivalOffsetTo);
if (location.To != newToId)
{
tour.Replace(location.To, newToId);
}
return cost;
}
}
return Weight.Zero; // insert failed, probably costs are too high (above given max parameter).
}
/// <summary>
/// Tries all 3Opt Moves for the neighbourhood of v_1 containing v_3.
/// </summary>
/// <returns></returns>
public bool Try3OptMoves(TSProblem problem, float[][] weights, Tour tour,
int v1, int v2, int v3, float[] weightsV3, int v4, float weightV1V2PlusV3V4, float weightV1V4, out float delta)
{
var v2ArrivalId = DirectedHelper.ExtractArrivalId(v2); // TODO: optimize this, extract all v2 info in one go.
var v2Id = DirectedHelper.ExtractId(v2);
var betweenV4V1Enumerator = tour.Between(v4, v1).GetEnumerator();
if (betweenV4V1Enumerator.MoveNext())
{
var v5 = betweenV4V1Enumerator.Current;
if (v5 != v1)
{
while (betweenV4V1Enumerator.MoveNext())
{
var v6 = betweenV4V1Enumerator.Current;
//var weightV3V6 = weightsV3[v6];
var v6Id = DirectedHelper.ExtractId(v6); // TODO: optimize this, extract all v6 info in one go.
var v6ArrivalId = DirectedHelper.ExtractArrivalId(v6);
var v5DepartureId = DirectedHelper.ExtractDepartureId(v5);
var weightV3V6 = weightsV3[v6ArrivalId];
//var weightV5V2 = weights[v5][v2];
var weightV5V2 = weights[v5DepartureId][v2ArrivalId];
//var weightV5V6 = weights[v5][v6];
var weightV5V6 = weights[v5DepartureId][v6ArrivalId];
if (v6Id == problem.First && !problem.Last.HasValue)
{ // set to zero if not closed.
weightV3V6 = 0;
weightV5V6 = 0;
}
if (v2Id == problem.First && !problem.Last.HasValue)
{ // set to zero if not closed.
weightV5V2 = 0;
}
// calculate the total weight of the 'new' arcs.
var weightNew = weightV1V4 + weightV3V6 + weightV5V2;
// calculate the total weights.
var weight = weightV1V2PlusV3V4 + weightV5V6;
if (weight - weightNew > _epsilon)
{ // actually do replace the vertices.
var countBefore = tour.Count;
delta = weightNew - weight;
tour.ReplaceEdgeFrom(v1, v4);
tour.ReplaceEdgeFrom(v3, v6);
tour.ReplaceEdgeFrom(v5, v2);
//int count_after = route.Count;
// set bits.
this.Set(problem, v3, false);
this.Set(problem, v5, false);
return(true); // move succeeded.
}
v5 = v6;
}
}
}
delta = 0;
return(false);
}
/// <summary>
/// Applies this operator.
/// </summary>
public bool Apply(TSProblem problem, TSPObjective objective, Tour solution, out float delta)
{
if (problem.Weights.Length <= 2)
{
delta = 0;
return(false);
}
var weights = problem.Weights;
delta = 0;
// test switching directions in random order.
if (_pool == null || solution.Count != _pool.Size)
{ // create a new pool.
_pool = new RandomPool(solution.Count);
}
else
{ // just reset the existing one.
_pool.Reset();
}
while (_pool.MoveNext())
{
var previous = solution.GetDirectedId(_pool.Current);
var previousDepartureId = DirectedHelper.ExtractDepartureId(previous);
var current = solution.GetNeigbour(previous);
if (current == Constants.NOT_SET)
{ // last of open.
continue;
}
var next = solution.GetNeigbour(current);
var nextArrivalId = Constants.NOT_SET;
if (next != Constants.NOT_SET)
{
nextArrivalId = DirectedHelper.ExtractArrivalId(next);
}
int currentTurn, currentId, currentArrivalId, currentDepartureId;
DirectedHelper.ExtractAll(current, out currentArrivalId, out currentDepartureId, out currentId, out currentTurn);
var weightBefore = weights[previousDepartureId][currentArrivalId];
var weightAfter = float.MaxValue;
var newDirectedId = Constants.NOT_SET;
if (next == Constants.NOT_SET)
{ // there is no next, only one option here:
// 0 or 1: arrival id offset = 0 OR
// 2 or 3: arrival id offset = 1
if (currentArrivalId % 2 == 0)
{ // check turn = 2.
weightAfter = weights[previousDepartureId][currentArrivalId + 1];
if (weightAfter < weightBefore)
{ // do the switch.
newDirectedId = DirectedHelper.BuildDirectedId(currentId, 2);
}
}
else
{ // check turn = 0
weightAfter = weights[previousDepartureId][currentArrivalId - 1];
if (weightAfter < weightBefore)
{ // do the switch.
newDirectedId = DirectedHelper.BuildDirectedId(currentId, 0);
}
}
}
else
{ // three options left, excluding the current one of 4.
weightBefore += weights[currentDepartureId][nextArrivalId];
weightBefore += problem.TurnPenalties[currentTurn];
currentArrivalId = currentArrivalId - (currentArrivalId % 2);
currentDepartureId = currentDepartureId - (currentDepartureId % 2);
for (var i = 0; i < 4; i++)
{
if (i == currentTurn)
{
continue;
}
int arrivalOffset, departureOffset;
DirectedHelper.ExtractOffset(i, out arrivalOffset, out departureOffset);
var newWeightAfter = weights[previousDepartureId][currentArrivalId + arrivalOffset]
+ weights[currentDepartureId + departureOffset][nextArrivalId]
+ problem.TurnPenalties[i];
if (newWeightAfter < weightAfter &&
newWeightAfter < weightBefore)
{
newDirectedId = DirectedHelper.BuildDirectedId(currentId, i);
weightAfter = newWeightAfter;
}
}
}
// switch if a new directed if was found.
if (newDirectedId != Constants.NOT_SET)
{
delta = weightAfter - weightBefore; // negative when improvement.
solution.Replace(current, newDirectedId);
}
}
return(delta < 0);
}