[8670] | 1 | #region License Information
|
---|
| 2 | /* HeuristicLab
|
---|
| 3 | * Copyright (C) 2002-2010 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
|
---|
| 4 | *
|
---|
| 5 | * This file is part of HeuristicLab.
|
---|
| 6 | *
|
---|
| 7 | * HeuristicLab is free software: you can redistribute it and/or modify
|
---|
| 8 | * it under the terms of the GNU General Public License as published by
|
---|
| 9 | * the Free Software Foundation, either version 3 of the License, or
|
---|
| 10 | * (at your option) any later version.
|
---|
| 11 | *
|
---|
| 12 | * HeuristicLab is distributed in the hope that it will be useful,
|
---|
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
---|
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
---|
| 15 | * GNU General Public License for more details.
|
---|
| 16 | *
|
---|
| 17 | * You should have received a copy of the GNU General Public License
|
---|
| 18 | * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
|
---|
| 19 | */
|
---|
| 20 | #endregion
|
---|
| 21 |
|
---|
| 22 | using System;
|
---|
| 23 | using System.Collections.Generic;
|
---|
| 24 | using HeuristicLab.Core;
|
---|
| 25 | using HeuristicLab.Data;
|
---|
| 26 | using HeuristicLab.Encodings.PermutationEncoding;
|
---|
| 27 | using HeuristicLab.Optimization;
|
---|
| 28 | using HeuristicLab.Parameters;
|
---|
| 29 | using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
|
---|
| 30 | using HeuristicLab.Common;
|
---|
| 31 | using HeuristicLab.Problems.VehicleRouting.Interfaces;
|
---|
| 32 | using HeuristicLab.Problems.VehicleRouting.ProblemInstances;
|
---|
| 33 | using HeuristicLab.Problems.VehicleRouting.Variants;
|
---|
| 34 | using HeuristicLab.Problems.VehicleRouting.Encodings.Potvin;
|
---|
| 35 | using HeuristicLab.Problems.VehicleRouting;
|
---|
| 36 |
|
---|
| 37 | namespace HeuristicLab.PDPSimulation.Operators {
|
---|
| 38 | [Item("DynPushForwardInsertionCreator", "Creates a randomly initialized VRP solution.")]
|
---|
| 39 | [StorableClass]
|
---|
| 40 | public sealed class DynPushForwardInsertionCreator : PotvinCreator, IStochasticOperator {
|
---|
| 41 | #region IStochasticOperator Members
|
---|
| 42 | public ILookupParameter<IRandom> RandomParameter {
|
---|
| 43 | get { return (LookupParameter<IRandom>)Parameters["Random"]; }
|
---|
| 44 | }
|
---|
| 45 | #endregion
|
---|
| 46 |
|
---|
| 47 | public IValueParameter<DoubleValue> Alpha {
|
---|
| 48 | get { return (IValueParameter<DoubleValue>)Parameters["Alpha"]; }
|
---|
| 49 | }
|
---|
| 50 | public IValueParameter<DoubleValue> AlphaVariance {
|
---|
| 51 | get { return (IValueParameter<DoubleValue>)Parameters["AlphaVariance"]; }
|
---|
| 52 | }
|
---|
| 53 | public IValueParameter<DoubleValue> Beta {
|
---|
| 54 | get { return (IValueParameter<DoubleValue>)Parameters["Beta"]; }
|
---|
| 55 | }
|
---|
| 56 | public IValueParameter<DoubleValue> BetaVariance {
|
---|
| 57 | get { return (IValueParameter<DoubleValue>)Parameters["BetaVariance"]; }
|
---|
| 58 | }
|
---|
| 59 | public IValueParameter<DoubleValue> Gamma {
|
---|
| 60 | get { return (IValueParameter<DoubleValue>)Parameters["Gamma"]; }
|
---|
| 61 | }
|
---|
| 62 | public IValueParameter<DoubleValue> GammaVariance {
|
---|
| 63 | get { return (IValueParameter<DoubleValue>)Parameters["GammaVariance"]; }
|
---|
| 64 | }
|
---|
| 65 |
|
---|
| 66 | [StorableConstructor]
|
---|
| 67 | private DynPushForwardInsertionCreator(bool deserializing) : base(deserializing) { }
|
---|
| 68 |
|
---|
| 69 | public DynPushForwardInsertionCreator()
|
---|
| 70 | : base() {
|
---|
| 71 | Parameters.Add(new LookupParameter<IRandom>("Random", "The pseudo random number generator."));
|
---|
| 72 | Parameters.Add(new ValueParameter<DoubleValue>("Alpha", "The alpha value.", new DoubleValue(0.7)));
|
---|
| 73 | Parameters.Add(new ValueParameter<DoubleValue>("AlphaVariance", "The alpha variance.", new DoubleValue(0.5)));
|
---|
| 74 | Parameters.Add(new ValueParameter<DoubleValue>("Beta", "The beta value.", new DoubleValue(0.1)));
|
---|
| 75 | Parameters.Add(new ValueParameter<DoubleValue>("BetaVariance", "The beta variance.", new DoubleValue(0.07)));
|
---|
| 76 | Parameters.Add(new ValueParameter<DoubleValue>("Gamma", "The gamma value.", new DoubleValue(0.2)));
|
---|
| 77 | Parameters.Add(new ValueParameter<DoubleValue>("GammaVariance", "The gamma variance.", new DoubleValue(0.14)));
|
---|
| 78 | }
|
---|
| 79 |
|
---|
| 80 | public override IDeepCloneable Clone(Cloner cloner) {
|
---|
| 81 | return new DynPushForwardInsertionCreator(this, cloner);
|
---|
| 82 | }
|
---|
| 83 |
|
---|
| 84 | private DynPushForwardInsertionCreator(DynPushForwardInsertionCreator original, Cloner cloner)
|
---|
| 85 | : base(original, cloner) {
|
---|
| 86 | }
|
---|
| 87 |
|
---|
| 88 | // use the Box-Mueller transform in the polar form to generate a N(0,1) random variable out of two uniformly distributed random variables
|
---|
| 89 | private static double Gauss(IRandom random) {
|
---|
| 90 | double u = 0.0, v = 0.0, s = 0.0;
|
---|
| 91 | do {
|
---|
| 92 | u = (random.NextDouble() * 2) - 1;
|
---|
| 93 | v = (random.NextDouble() * 2) - 1;
|
---|
| 94 | s = Math.Sqrt(u * u + v * v);
|
---|
| 95 | } while (s < Double.Epsilon || s > 1);
|
---|
| 96 | return u * Math.Sqrt((-2.0 * Math.Log(s)) / s);
|
---|
| 97 | }
|
---|
| 98 |
|
---|
| 99 | private static double N(double mu, double sigma, IRandom random) {
|
---|
| 100 | return mu + (sigma * Gauss(random)); // transform the random variable sampled from N(0,1) to N(mu,sigma)
|
---|
| 101 | }
|
---|
| 102 |
|
---|
| 103 | private static double GetDistance(int start, int end, IVRPProblemInstance problemInstance, PotvinEncoding solution) {
|
---|
| 104 | double distance = 0.0;
|
---|
| 105 |
|
---|
| 106 | if (problemInstance is DynPDPProblemInstance) {
|
---|
| 107 | distance = (problemInstance as DynPDPProblemInstance).GetDistance(start, end);
|
---|
| 108 | }
|
---|
| 109 | else if (problemInstance.UseDistanceMatrix.Value && problemInstance.DistanceMatrix != null) {
|
---|
| 110 | distance = problemInstance.DistanceMatrix[start, end];
|
---|
| 111 | } else {
|
---|
| 112 | double startX = problemInstance.Coordinates[start, 0];
|
---|
| 113 | double startY = problemInstance.Coordinates[start, 1];
|
---|
| 114 |
|
---|
| 115 | double endX = problemInstance.Coordinates[end, 0];
|
---|
| 116 | double endY = problemInstance.Coordinates[end, 1];
|
---|
| 117 |
|
---|
| 118 | distance =
|
---|
| 119 | Math.Sqrt(
|
---|
| 120 | Math.Pow(startX - endX, 2) +
|
---|
| 121 | Math.Pow(startY - endY, 2));
|
---|
| 122 | }
|
---|
| 123 |
|
---|
| 124 | return distance;
|
---|
| 125 | }
|
---|
| 126 |
|
---|
| 127 | private static double GetCosts(int customer, int vehicle, IVRPProblemInstance problemInstance,
|
---|
| 128 | Dictionary<int, List<int>> vehicles, Dictionary<int, Tour> vehicleTours, List<bool> vehicleUsed, PotvinEncoding solution,
|
---|
| 129 | double alpha, double beta, double gamma, out bool feasible, out bool existingRoute) {
|
---|
| 130 | int depotCount = 1;
|
---|
| 131 | IMultiDepotProblemInstance mdp = problemInstance as IMultiDepotProblemInstance;
|
---|
| 132 | if (mdp != null) {
|
---|
| 133 | depotCount = mdp.Depots.Value;
|
---|
| 134 | }
|
---|
| 135 |
|
---|
| 136 | feasible = true;
|
---|
| 137 |
|
---|
| 138 | double distance = GetDistance(vehicle, customer + depotCount - 1, problemInstance, solution);
|
---|
| 139 | if (vehicleUsed != null) {
|
---|
| 140 | existingRoute = vehicleUsed[vehicle];
|
---|
| 141 | } else {
|
---|
| 142 | existingRoute = true;
|
---|
| 143 | }
|
---|
| 144 |
|
---|
| 145 | double dueTime = 0;
|
---|
| 146 | if (problemInstance is ITimeWindowedProblemInstance) {
|
---|
| 147 | ITimeWindowedProblemInstance vrptw = problemInstance as ITimeWindowedProblemInstance;
|
---|
| 148 | dueTime = vrptw.DueTime[customer + depotCount - 1];
|
---|
| 149 | }
|
---|
| 150 |
|
---|
| 151 | if (vehicleTours.ContainsKey(vehicle)) {
|
---|
| 152 | Tour tour = vehicleTours[vehicle];
|
---|
| 153 |
|
---|
| 154 | IPickupAndDeliveryProblemInstance pdp = problemInstance as IPickupAndDeliveryProblemInstance;
|
---|
| 155 | if (pdp != null && pdp.GetPickupDeliveryLocation(customer) > 0) {
|
---|
| 156 | solution.InsertPair(tour, customer, pdp.GetPickupDeliveryLocation(customer), problemInstance);
|
---|
| 157 | } else {
|
---|
| 158 | tour.Stops.Insert(solution.FindBestInsertionPlace(tour, customer), customer);
|
---|
| 159 | }
|
---|
| 160 |
|
---|
| 161 | feasible = problemInstance.TourFeasible(tour, solution);
|
---|
| 162 |
|
---|
| 163 | tour.Stops.Remove(customer);
|
---|
| 164 | if (pdp != null && pdp.GetPickupDeliveryLocation(customer) > 0) {
|
---|
| 165 | tour.Stops.Remove(pdp.GetPickupDeliveryLocation(customer));
|
---|
| 166 | }
|
---|
| 167 | }
|
---|
| 168 | else if (problemInstance is ITimeWindowedProblemInstance) {
|
---|
| 169 | IPickupAndDeliveryProblemInstance pdp = problemInstance as IPickupAndDeliveryProblemInstance;
|
---|
| 170 | ITimeWindowedProblemInstance vrptw = problemInstance as ITimeWindowedProblemInstance;
|
---|
| 171 | double time = vrptw.ReadyTime[vehicle];
|
---|
| 172 | time += distance;
|
---|
| 173 | if (time > dueTime) {
|
---|
| 174 | feasible = false;
|
---|
| 175 | } else {
|
---|
| 176 | time += vrptw.ServiceTime[customer - 1];
|
---|
| 177 | if (pdp != null && pdp.GetPickupDeliveryLocation(customer) > 0) {
|
---|
| 178 | int targetCustomer = pdp.GetPickupDeliveryLocation(customer);
|
---|
| 179 | time += GetDistance(customer + depotCount - 1, targetCustomer + depotCount - 1, problemInstance, solution);
|
---|
| 180 | if (time > vrptw.DueTime[targetCustomer + depotCount - 1]) {
|
---|
| 181 | feasible = false;
|
---|
| 182 | }
|
---|
| 183 |
|
---|
| 184 | time += vrptw.ServiceTime[targetCustomer - 1];
|
---|
| 185 | time += GetDistance(targetCustomer + depotCount - 1, vehicle, problemInstance, solution);
|
---|
| 186 |
|
---|
| 187 | if (time > vrptw.DueTime[vehicle]) {
|
---|
| 188 | feasible = false;
|
---|
| 189 | }
|
---|
| 190 | } else {
|
---|
| 191 | time += GetDistance(customer + depotCount - 1, vehicle, problemInstance, solution);
|
---|
| 192 | if (time > vrptw.DueTime[vehicle]) {
|
---|
| 193 | feasible = false;
|
---|
| 194 | }
|
---|
| 195 | }
|
---|
| 196 | }
|
---|
| 197 | }
|
---|
| 198 |
|
---|
| 199 | if (problemInstance is IHeterogenousCapacitatedProblemInstance) {
|
---|
| 200 | IHeterogenousCapacitatedProblemInstance cvrp = problemInstance as IHeterogenousCapacitatedProblemInstance;
|
---|
| 201 | double demand = problemInstance.GetDemand(customer);
|
---|
| 202 | if (demand > cvrp.Capacity[vehicle])
|
---|
| 203 | feasible = false;
|
---|
| 204 | } else if (problemInstance is IHomogenousCapacitatedProblemInstance) {
|
---|
| 205 | IHomogenousCapacitatedProblemInstance cvrp = problemInstance as IHomogenousCapacitatedProblemInstance;
|
---|
| 206 | double demand = problemInstance.GetDemand(customer);
|
---|
| 207 | if (demand > cvrp.Capacity.Value)
|
---|
| 208 | feasible = false;
|
---|
| 209 | }
|
---|
| 210 |
|
---|
| 211 | double x0 = problemInstance.Coordinates[vehicle, 0];
|
---|
| 212 | double y0 = problemInstance.Coordinates[vehicle, 1];
|
---|
| 213 | double dist;
|
---|
| 214 | if (problemInstance.Coordinates[customer + depotCount - 1, 0] < x0)
|
---|
| 215 | dist = -distance;
|
---|
| 216 | else
|
---|
| 217 | dist = distance;
|
---|
| 218 | double polarAngle = (dist != 0 ? (Math.Asin((problemInstance.Coordinates[customer + depotCount - 1, 1] - y0) / dist) / 360 * dist) : 0);
|
---|
| 219 |
|
---|
| 220 | if (problemInstance is ITimeWindowedProblemInstance) {
|
---|
| 221 | ITimeWindowedProblemInstance vrptw = problemInstance as ITimeWindowedProblemInstance;
|
---|
| 222 |
|
---|
| 223 | if (dueTime == double.MaxValue)
|
---|
| 224 | dueTime = 0;
|
---|
| 225 | else {
|
---|
| 226 | dueTime -= vrptw.ReadyTime[vehicle];
|
---|
| 227 | }
|
---|
| 228 | }
|
---|
| 229 |
|
---|
| 230 | double cost = alpha * distance + // distance 0 <-> City[i]
|
---|
| 231 | -beta * dueTime + // latest arrival time
|
---|
| 232 | -gamma * polarAngle; // polar angle
|
---|
| 233 |
|
---|
| 234 | if (vehicleUsed != null) {
|
---|
| 235 | if (!vehicleUsed[vehicle])
|
---|
| 236 | cost += problemInstance.FleetUsageFactor.Value;
|
---|
| 237 | }
|
---|
| 238 |
|
---|
| 239 | return cost;
|
---|
| 240 | }
|
---|
| 241 |
|
---|
| 242 | private static int GetNearestDepot(IVRPProblemInstance problemInstance, List<int> depots, int customer,
|
---|
| 243 | Dictionary<int, List<int>> vehicles, Dictionary<int, Tour> vehicleTours, List<bool> vehicleUsed, PotvinEncoding solution,
|
---|
| 244 | double alpha, double beta, double gamma, out double minCost, out bool bound, out bool bestExistingRoute) {
|
---|
| 245 | int nearest = -1;
|
---|
| 246 | minCost = double.MaxValue;
|
---|
| 247 | bestExistingRoute = false;
|
---|
| 248 |
|
---|
| 249 | bool bestFeasible = false;
|
---|
| 250 | int feasibleCount = 0;
|
---|
| 251 | foreach (int depot in depots) {
|
---|
| 252 | int vehicle = vehicles[depot][0];
|
---|
| 253 |
|
---|
| 254 | bool existingRoute;
|
---|
| 255 | bool feasible;
|
---|
| 256 | double cost = GetCosts(
|
---|
| 257 | customer, vehicle,
|
---|
| 258 | problemInstance, vehicles, vehicleTours, vehicleUsed,
|
---|
| 259 | solution, alpha, beta, gamma, out feasible, out existingRoute);
|
---|
| 260 |
|
---|
| 261 | if (feasible)
|
---|
| 262 | feasibleCount++;
|
---|
| 263 |
|
---|
| 264 | if ((feasible && !bestFeasible) ||
|
---|
| 265 | (feasible == bestFeasible && existingRoute && !bestExistingRoute) ||
|
---|
| 266 | (feasible == bestFeasible && existingRoute == bestExistingRoute && cost < minCost)) {
|
---|
| 267 | minCost = cost;
|
---|
| 268 | nearest = depot;
|
---|
| 269 | bestFeasible = feasible;
|
---|
| 270 | bestExistingRoute = existingRoute;
|
---|
| 271 | }
|
---|
| 272 | }
|
---|
| 273 |
|
---|
| 274 | bound = (feasibleCount == 1);
|
---|
| 275 |
|
---|
| 276 | return nearest;
|
---|
| 277 | }
|
---|
| 278 |
|
---|
| 279 | private static List<int> SortCustomers(IVRPProblemInstance problemInstance, List<int> customers, List<int> depots,
|
---|
| 280 | Dictionary<int, int> depotAssignment, Dictionary<int, int> customerBinding,
|
---|
| 281 | Dictionary<int, List<int>> vehicles, Dictionary<int, Tour> vehicleTours, List<bool> vehicleUsed, PotvinEncoding solution,
|
---|
| 282 | double alpha, double beta, double gamma) {
|
---|
| 283 | List<int> sortedCustomers = new List<int>();
|
---|
| 284 | depotAssignment.Clear();
|
---|
| 285 | customerBinding.Clear();
|
---|
| 286 |
|
---|
| 287 | List<bool> boundList = new List<bool>();
|
---|
| 288 | List<bool> existingRouteList = new List<bool>();
|
---|
| 289 | List<double> costList = new List<double>();
|
---|
| 290 |
|
---|
| 291 | for (int i = 0; i < customers.Count; i++) {
|
---|
| 292 | double cost;
|
---|
| 293 | bool bound;
|
---|
| 294 | bool existingRoute;
|
---|
| 295 | int depot = GetNearestDepot(problemInstance, depots, customers[i], vehicles, vehicleTours, vehicleUsed, solution,
|
---|
| 296 | alpha, beta, gamma,
|
---|
| 297 | out cost, out bound, out existingRoute);
|
---|
| 298 | depotAssignment[customers[i]] = depot;
|
---|
| 299 | if (bound) {
|
---|
| 300 | customerBinding.Add(customers[i], depot);
|
---|
| 301 | }
|
---|
| 302 |
|
---|
| 303 | int index = 0;
|
---|
| 304 | while (index < costList.Count &&
|
---|
| 305 | ((!bound && boundList[index]) ||
|
---|
| 306 | (bound == boundList[index] && !existingRoute && existingRouteList[index]) ||
|
---|
| 307 | (bound == boundList[index] && existingRoute == existingRouteList[index] && costList[index] < cost)))
|
---|
| 308 | index++;
|
---|
| 309 |
|
---|
| 310 | costList.Insert(index, cost);
|
---|
| 311 | boundList.Insert(index, bound);
|
---|
| 312 | existingRouteList.Insert(index, existingRoute);
|
---|
| 313 | sortedCustomers.Insert(index, customers[i]);
|
---|
| 314 | }
|
---|
| 315 |
|
---|
| 316 | return sortedCustomers;
|
---|
| 317 | }
|
---|
| 318 |
|
---|
| 319 | private static bool RemoveUnusedDepots(List<int> depots, Dictionary<int, List<int>> vehicles) {
|
---|
| 320 | List<int> toBeRemoved = new List<int>();
|
---|
| 321 |
|
---|
| 322 | foreach (int depot in depots) {
|
---|
| 323 | if (vehicles[depot].Count == 0)
|
---|
| 324 | toBeRemoved.Add(depot);
|
---|
| 325 | }
|
---|
| 326 |
|
---|
| 327 | foreach (int depot in toBeRemoved) {
|
---|
| 328 | depots.Remove(depot);
|
---|
| 329 | vehicles.Remove(depot);
|
---|
| 330 | }
|
---|
| 331 |
|
---|
| 332 | return toBeRemoved.Count > 0;
|
---|
| 333 | }
|
---|
| 334 |
|
---|
| 335 | private static Dictionary<int, Tour> CreateInitialTours(IVRPProblemInstance problemInstance, Dictionary<int, List<int>> vehicles, PotvinEncoding result) {
|
---|
| 336 | Dictionary<int, Tour> vehicleTours = new Dictionary<int, Tour>();
|
---|
| 337 | IPickupAndDeliveryProblemInstance pdp = problemInstance as IPickupAndDeliveryProblemInstance;
|
---|
| 338 |
|
---|
| 339 | int currentVehicle;
|
---|
| 340 |
|
---|
| 341 | for (int i = 1; i <= problemInstance.Cities.Value; i++) {
|
---|
| 342 | if (pdp != null && pdp.GetPickupDeliveryLocation(i) <= 0) {
|
---|
| 343 | currentVehicle = -pdp.GetPickupDeliveryLocation(i);
|
---|
| 344 | foreach (int depot in vehicles.Keys) {
|
---|
| 345 | if (vehicles[depot].Contains(currentVehicle)) {
|
---|
| 346 | vehicles[depot].Remove(currentVehicle);
|
---|
| 347 | vehicles[depot].Insert(0, currentVehicle);
|
---|
| 348 | break;
|
---|
| 349 | }
|
---|
| 350 | }
|
---|
| 351 |
|
---|
| 352 | Tour tour;
|
---|
| 353 |
|
---|
| 354 | if (!vehicleTours.ContainsKey(currentVehicle)) {
|
---|
| 355 | tour = new Tour();
|
---|
| 356 | result.Tours.Add(tour);
|
---|
| 357 | vehicleTours[currentVehicle] = tour;
|
---|
| 358 | result.VehicleAssignment[result.Tours.Count - 1] = currentVehicle;
|
---|
| 359 | } else {
|
---|
| 360 | tour = vehicleTours[currentVehicle];
|
---|
| 361 | }
|
---|
| 362 |
|
---|
| 363 | tour.Stops.Add(i);
|
---|
| 364 | }
|
---|
| 365 | }
|
---|
| 366 |
|
---|
| 367 | foreach (int vehicle in vehicleTours.Keys) {
|
---|
| 368 | Tour vehicleTour = vehicleTours[vehicle];
|
---|
| 369 | List<int> customers = new List<int>(vehicleTour.Stops);
|
---|
| 370 | vehicleTour.Stops.Clear();
|
---|
| 371 |
|
---|
| 372 | if (problemInstance is DynPDPProblemInstance &&
|
---|
| 373 | (problemInstance as DynPDPProblemInstance).CurrentPlan != null) {
|
---|
| 374 | PotvinEncoding plan = (problemInstance as DynPDPProblemInstance).CurrentPlan;
|
---|
| 375 | Tour planTour = plan.Tours.Find(t => plan.GetVehicleAssignment(plan.Tours.IndexOf(t)) == vehicle);
|
---|
| 376 |
|
---|
| 377 | customers.Sort((x, y) => planTour.Stops.IndexOf(x).CompareTo(planTour.Stops.IndexOf(y)));
|
---|
| 378 | foreach (int customer in customers)
|
---|
| 379 | vehicleTour.Stops.Add(customer);
|
---|
| 380 | } else {
|
---|
| 381 | for (int i = 0; i < customers.Count; i++) {
|
---|
| 382 | int stop = result.FindBestInsertionPlace(vehicleTour, customers[i]);
|
---|
| 383 | vehicleTour.Stops.Insert(stop, customers[i]);
|
---|
| 384 | }
|
---|
| 385 | }
|
---|
| 386 | }
|
---|
| 387 |
|
---|
| 388 | return vehicleTours;
|
---|
| 389 | }
|
---|
| 390 |
|
---|
| 391 | public static PotvinEncoding CreateSolution(IVRPProblemInstance problemInstance, IRandom random, List<bool> vehicleUsed,
|
---|
| 392 | double alphaValue = 0.7, double betaValue = 0.1, double gammaValue = 0.2,
|
---|
| 393 | double alphaVariance = 0.5, double betaVariance = 0.07, double gammaVariance = 0.14) {
|
---|
| 394 | PotvinEncoding result = new PotvinEncoding(problemInstance);
|
---|
| 395 |
|
---|
| 396 | IPickupAndDeliveryProblemInstance pdp = problemInstance as IPickupAndDeliveryProblemInstance;
|
---|
| 397 | IMultiDepotProblemInstance mdp = problemInstance as IMultiDepotProblemInstance;
|
---|
| 398 |
|
---|
| 399 | if (mdp != null) {
|
---|
| 400 | for (int i = 0; i < result.VehicleAssignment.Length; i++) {
|
---|
| 401 | result.VehicleAssignment[i] = -1;
|
---|
| 402 | }
|
---|
| 403 | }
|
---|
| 404 |
|
---|
| 405 | double alpha, beta, gamma;
|
---|
| 406 | lock (random) {
|
---|
| 407 | alpha = N(alphaValue, Math.Sqrt(alphaVariance), random);
|
---|
| 408 | beta = N(betaValue, Math.Sqrt(betaVariance), random);
|
---|
| 409 | gamma = N(gammaValue, Math.Sqrt(gammaVariance), random);
|
---|
| 410 | }
|
---|
| 411 |
|
---|
| 412 | #region initialization
|
---|
| 413 | List<int> unroutedCustomers = new List<int>();
|
---|
| 414 | for (int i = 1; i <= problemInstance.Cities.Value; i++) {
|
---|
| 415 | if (pdp == null || (problemInstance.GetDemand(i) >= 0) || (pdp.GetPickupDeliveryLocation(i) == i))
|
---|
| 416 | unroutedCustomers.Add(i);
|
---|
| 417 | }
|
---|
| 418 |
|
---|
| 419 | List<int> depots = new List<int>();
|
---|
| 420 | if (mdp != null) {
|
---|
| 421 | for (int i = 0; i < mdp.Depots.Value; i++) {
|
---|
| 422 | depots.Add(i);
|
---|
| 423 | }
|
---|
| 424 | } else {
|
---|
| 425 | depots.Add(0);
|
---|
| 426 | }
|
---|
| 427 |
|
---|
| 428 | Dictionary<int, List<int>> vehicles = new Dictionary<int, List<int>>();
|
---|
| 429 | foreach (int depot in depots) {
|
---|
| 430 | vehicles[depot] = new List<int>();
|
---|
| 431 |
|
---|
| 432 | int vehicleCount = problemInstance.Vehicles.Value;
|
---|
| 433 | if (mdp != null) {
|
---|
| 434 | for (int vehicle = 0; vehicle < mdp.VehicleDepotAssignment.Length; vehicle++) {
|
---|
| 435 | if (mdp.VehicleDepotAssignment[vehicle] == depot) {
|
---|
| 436 | vehicles[depot].Add(vehicle);
|
---|
| 437 | }
|
---|
| 438 | }
|
---|
| 439 | } else {
|
---|
| 440 | for (int vehicle = 0; vehicle < vehicleCount; vehicle++) {
|
---|
| 441 | vehicles[depot].Add(vehicle);
|
---|
| 442 | }
|
---|
| 443 | }
|
---|
| 444 |
|
---|
| 445 | if (vehicleUsed != null) {
|
---|
| 446 | vehicles[depot].Sort(delegate(int x, int y) {
|
---|
| 447 | if (vehicleUsed[x] && vehicleUsed[y])
|
---|
| 448 | return 0;
|
---|
| 449 | else if (vehicleUsed[x])
|
---|
| 450 | return -1;
|
---|
| 451 | else
|
---|
| 452 | return 1;
|
---|
| 453 | });
|
---|
| 454 | }
|
---|
| 455 | }
|
---|
| 456 |
|
---|
| 457 | Dictionary<int, Tour> vehicleTours = CreateInitialTours(problemInstance, vehicles, result);
|
---|
| 458 | RemoveUnusedDepots(depots, vehicles);
|
---|
| 459 | #endregion
|
---|
| 460 |
|
---|
| 461 | #region route unrouted
|
---|
| 462 | if (unroutedCustomers.Count > 0) {
|
---|
| 463 | Tour tour;
|
---|
| 464 | int currentDepot;
|
---|
| 465 | int currentVehicle;
|
---|
| 466 | Dictionary<int, int> depotAssignment = new Dictionary<int, int>();
|
---|
| 467 |
|
---|
| 468 | //# sort customers globally - start new tour
|
---|
| 469 | Dictionary<int, int> customerBinding = new Dictionary<int, int>();
|
---|
| 470 | unroutedCustomers = SortCustomers(
|
---|
| 471 | problemInstance, unroutedCustomers, depots, depotAssignment, customerBinding,
|
---|
| 472 | vehicles, vehicleTours, vehicleUsed, result,
|
---|
| 473 | alpha, beta, gamma);
|
---|
| 474 |
|
---|
| 475 | int currentCustomer = unroutedCustomers[0];
|
---|
| 476 | currentDepot = depotAssignment[currentCustomer];
|
---|
| 477 | currentVehicle = vehicles[currentDepot][0];
|
---|
| 478 | vehicles[currentDepot].RemoveAt(0);
|
---|
| 479 | RemoveUnusedDepots(depots, vehicles);
|
---|
| 480 |
|
---|
| 481 | if (!vehicleTours.ContainsKey(currentVehicle)) {
|
---|
| 482 | tour = new Tour();
|
---|
| 483 | result.Tours.Add(tour);
|
---|
| 484 | result.VehicleAssignment[result.Tours.Count - 1] = currentVehicle;
|
---|
| 485 |
|
---|
| 486 | unroutedCustomers.Remove(currentCustomer);
|
---|
| 487 | tour.Stops.Add(currentCustomer);
|
---|
| 488 | if (pdp != null && pdp.GetPickupDeliveryLocation(currentCustomer) != currentCustomer) {
|
---|
| 489 | tour.Stops.Add(pdp.GetPickupDeliveryLocation(currentCustomer));
|
---|
| 490 | }
|
---|
| 491 | } else {
|
---|
| 492 | tour = vehicleTours[currentVehicle];
|
---|
| 493 | }
|
---|
| 494 |
|
---|
| 495 | while (unroutedCustomers.Count > 0) {
|
---|
| 496 | double minimumCost = double.MaxValue;
|
---|
| 497 | bool bestBoundToRoute = false;
|
---|
| 498 | int customer = -1;
|
---|
| 499 | int indexOfMinimumCost = -1;
|
---|
| 500 | int indexOfMinimumCost2 = -1;
|
---|
| 501 |
|
---|
| 502 | foreach (int unrouted in unroutedCustomers) {
|
---|
| 503 | bool boundToRoute = customerBinding.ContainsKey(unrouted) && customerBinding[unrouted] == currentDepot;
|
---|
| 504 |
|
---|
| 505 | VRPEvaluation eval = problemInstance.EvaluateTour(tour, result);
|
---|
| 506 | double originalCosts = eval.Quality;
|
---|
| 507 |
|
---|
| 508 | for (int i = 0; i <= tour.Stops.Count; i++) {
|
---|
| 509 | tour.Stops.Insert(i, unrouted);
|
---|
| 510 | eval = problemInstance.EvaluateTour(tour, result);
|
---|
| 511 | double tourCost = eval.Quality - originalCosts;
|
---|
| 512 |
|
---|
| 513 | if (pdp != null && pdp.GetPickupDeliveryLocation(unrouted) != unrouted) {
|
---|
| 514 | for (int j = i + 1; j <= tour.Stops.Count; j++) {
|
---|
| 515 | bool feasible;
|
---|
| 516 | double cost = tourCost +
|
---|
| 517 | problemInstance.GetInsertionCosts(eval, result, pdp.GetPickupDeliveryLocation(unrouted), 0, j, out feasible);
|
---|
| 518 | if ((cost < minimumCost || (!bestBoundToRoute && boundToRoute)) && (boundToRoute || !bestBoundToRoute) && feasible) {
|
---|
| 519 | customer = unrouted;
|
---|
| 520 | minimumCost = cost;
|
---|
| 521 | indexOfMinimumCost = i;
|
---|
| 522 | indexOfMinimumCost2 = j;
|
---|
| 523 | bestBoundToRoute = boundToRoute;
|
---|
| 524 | }
|
---|
| 525 | }
|
---|
| 526 | } else {
|
---|
| 527 | double cost = tourCost;
|
---|
| 528 | bool feasible = problemInstance.Feasible(eval);
|
---|
| 529 | if ((cost < minimumCost || (!bestBoundToRoute && boundToRoute)) && (boundToRoute || !bestBoundToRoute) && feasible) {
|
---|
| 530 | customer = unrouted;
|
---|
| 531 | minimumCost = cost;
|
---|
| 532 | indexOfMinimumCost = i;
|
---|
| 533 | bestBoundToRoute = boundToRoute;
|
---|
| 534 | }
|
---|
| 535 | }
|
---|
| 536 |
|
---|
| 537 | tour.Stops.RemoveAt(i);
|
---|
| 538 | }
|
---|
| 539 | }
|
---|
| 540 |
|
---|
| 541 | if (indexOfMinimumCost == -1 && vehicles.Count == 0) {
|
---|
| 542 | indexOfMinimumCost = tour.Stops.Count;
|
---|
| 543 | indexOfMinimumCost2 = tour.Stops.Count + 1;
|
---|
| 544 | customer = unroutedCustomers[0];
|
---|
| 545 | }
|
---|
| 546 |
|
---|
| 547 | // insert customer if found
|
---|
| 548 | if (indexOfMinimumCost != -1) {
|
---|
| 549 | tour.Stops.Insert(indexOfMinimumCost, customer);
|
---|
| 550 | if (pdp != null && pdp.GetPickupDeliveryLocation(customer) != customer) {
|
---|
| 551 | tour.Stops.Insert(indexOfMinimumCost2, pdp.GetPickupDeliveryLocation(customer));
|
---|
| 552 | }
|
---|
| 553 | unroutedCustomers.Remove(customer);
|
---|
| 554 | } else { // no feasible customer found
|
---|
| 555 | //# sort customers globally - start new tour
|
---|
| 556 | unroutedCustomers = SortCustomers(
|
---|
| 557 | problemInstance, unroutedCustomers, depots, depotAssignment, customerBinding,
|
---|
| 558 | vehicles, vehicleTours, vehicleUsed, result,
|
---|
| 559 | alpha, beta, gamma);
|
---|
| 560 |
|
---|
| 561 | currentCustomer = unroutedCustomers[0];
|
---|
| 562 | currentDepot = depotAssignment[currentCustomer];
|
---|
| 563 | currentVehicle = vehicles[currentDepot][0];
|
---|
| 564 | vehicles[currentDepot].RemoveAt(0);
|
---|
| 565 | RemoveUnusedDepots(depots, vehicles);
|
---|
| 566 |
|
---|
| 567 | if (!vehicleTours.ContainsKey(currentVehicle)) {
|
---|
| 568 | tour = new Tour();
|
---|
| 569 | result.Tours.Add(tour);
|
---|
| 570 | result.VehicleAssignment[result.Tours.Count - 1] = currentVehicle;
|
---|
| 571 |
|
---|
| 572 | unroutedCustomers.Remove(currentCustomer);
|
---|
| 573 | tour.Stops.Add(currentCustomer);
|
---|
| 574 | if (pdp != null && pdp.GetPickupDeliveryLocation(currentCustomer) != currentCustomer) {
|
---|
| 575 | tour.Stops.Add(pdp.GetPickupDeliveryLocation(currentCustomer));
|
---|
| 576 | }
|
---|
| 577 | } else {
|
---|
| 578 | tour = vehicleTours[currentVehicle];
|
---|
| 579 | }
|
---|
| 580 | }
|
---|
| 581 | }
|
---|
| 582 | }
|
---|
| 583 | #endregion
|
---|
| 584 |
|
---|
| 585 | #region assign vehicles
|
---|
| 586 | if (mdp != null) {
|
---|
| 587 | List<int> availableVehicles = new List<int>();
|
---|
| 588 | for (int i = 0; i < mdp.Vehicles.Value; i++)
|
---|
| 589 | availableVehicles.Add(i);
|
---|
| 590 |
|
---|
| 591 | for (int i = 0; i < result.VehicleAssignment.Length; i++) {
|
---|
| 592 | if (result.VehicleAssignment[i] != -1)
|
---|
| 593 | availableVehicles.Remove(result.VehicleAssignment[i]);
|
---|
| 594 | }
|
---|
| 595 |
|
---|
| 596 | for (int i = 0; i < result.VehicleAssignment.Length; i++) {
|
---|
| 597 | if (result.VehicleAssignment[i] == -1) {
|
---|
| 598 | result.VehicleAssignment[i] = availableVehicles[0];
|
---|
| 599 | availableVehicles.RemoveAt(0);
|
---|
| 600 | }
|
---|
| 601 | }
|
---|
| 602 | }
|
---|
| 603 | #endregion
|
---|
| 604 |
|
---|
| 605 | return result;
|
---|
| 606 | }
|
---|
| 607 |
|
---|
| 608 | public override IOperation Apply() {
|
---|
| 609 | List<bool> vehicleUsed = null;
|
---|
| 610 |
|
---|
| 611 | DynPDPProblemInstance instance = ProblemInstance as DynPDPProblemInstance;
|
---|
| 612 | if(instance != null) {
|
---|
| 613 | vehicleUsed = new List<bool>();
|
---|
| 614 | for (int i = 0; i < instance.VehicleUsed.Length; i++) {
|
---|
| 615 | vehicleUsed.Add(instance.VehicleUsed[i]);
|
---|
| 616 | }
|
---|
| 617 | }
|
---|
| 618 |
|
---|
| 619 | VRPToursParameter.ActualValue = CreateSolution(ProblemInstance, RandomParameter.ActualValue, vehicleUsed,
|
---|
| 620 | Alpha.Value.Value, Beta.Value.Value, Gamma.Value.Value,
|
---|
| 621 | AlphaVariance.Value.Value, BetaVariance.Value.Value, GammaVariance.Value.Value);
|
---|
| 622 |
|
---|
| 623 | return base.Apply();
|
---|
| 624 | }
|
---|
| 625 | }
|
---|
| 626 | }
|
---|
| 627 |
|
---|