com.graphhopper.jsprit.examples.BuildAlgorithmFromScratch Maven / Gradle / Ivy
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package com.graphhopper.jsprit.examples;
import com.graphhopper.jsprit.analysis.toolbox.AlgorithmEventsRecorder;
import com.graphhopper.jsprit.core.algorithm.PrettyAlgorithmBuilder;
import com.graphhopper.jsprit.core.algorithm.SearchStrategy;
import com.graphhopper.jsprit.core.algorithm.VehicleRoutingAlgorithm;
import com.graphhopper.jsprit.core.algorithm.acceptor.GreedyAcceptance;
import com.graphhopper.jsprit.core.algorithm.listener.IterationStartsListener;
import com.graphhopper.jsprit.core.algorithm.module.RuinAndRecreateModule;
import com.graphhopper.jsprit.core.algorithm.recreate.*;
import com.graphhopper.jsprit.core.algorithm.ruin.RadialRuinStrategyFactory;
import com.graphhopper.jsprit.core.algorithm.ruin.RandomRuinStrategyFactory;
import com.graphhopper.jsprit.core.algorithm.ruin.RuinStrategy;
import com.graphhopper.jsprit.core.algorithm.ruin.distance.AvgServiceAndShipmentDistance;
import com.graphhopper.jsprit.core.algorithm.selector.SelectBest;
import com.graphhopper.jsprit.core.algorithm.state.StateManager;
import com.graphhopper.jsprit.core.analysis.SolutionAnalyser;
import com.graphhopper.jsprit.core.problem.Location;
import com.graphhopper.jsprit.core.problem.VehicleRoutingProblem;
import com.graphhopper.jsprit.core.problem.constraint.ConstraintManager;
import com.graphhopper.jsprit.core.problem.cost.TransportDistance;
import com.graphhopper.jsprit.core.problem.job.Job;
import com.graphhopper.jsprit.core.problem.solution.SolutionCostCalculator;
import com.graphhopper.jsprit.core.problem.solution.VehicleRoutingProblemSolution;
import com.graphhopper.jsprit.core.problem.solution.route.VehicleRoute;
import com.graphhopper.jsprit.core.problem.vehicle.FiniteFleetManagerFactory;
import com.graphhopper.jsprit.core.problem.vehicle.Vehicle;
import com.graphhopper.jsprit.core.problem.vehicle.VehicleFleetManager;
import com.graphhopper.jsprit.core.reporting.SolutionPrinter;
import com.graphhopper.jsprit.core.util.Solutions;
import com.graphhopper.jsprit.instance.reader.CordeauReader;
import com.graphhopper.jsprit.util.Examples;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
public class BuildAlgorithmFromScratch {
public static class MyBestStrategy extends AbstractInsertionStrategy {
private JobInsertionCostsCalculatorLight insertionCalculator;
public MyBestStrategy(VehicleRoutingProblem vrp, VehicleFleetManager fleetManager, StateManager stateManager, ConstraintManager constraintManager) {
super(vrp);
insertionCalculator = JobInsertionCostsCalculatorLightFactory.createStandardCalculator(vrp, fleetManager, stateManager, constraintManager);
}
@Override
public Collection insertUnassignedJobs(Collection vehicleRoutes, Collection unassignedJobs) {
List badJobs = new ArrayList();
List unassigned = new ArrayList(unassignedJobs);
Collections.shuffle(unassigned, random);
for (Job j : unassigned) {
InsertionData bestInsertionData = InsertionData.createEmptyInsertionData();
VehicleRoute bestRoute = null;
//look for inserting unassigned job into existing route
for (VehicleRoute r : vehicleRoutes) {
InsertionData insertionData = insertionCalculator.getInsertionData(j, r, bestInsertionData.getInsertionCost());
if (insertionData instanceof InsertionData.NoInsertionFound) continue;
if (insertionData.getInsertionCost() < bestInsertionData.getInsertionCost()) {
bestInsertionData = insertionData;
bestRoute = r;
}
}
//try whole new route
VehicleRoute empty = VehicleRoute.emptyRoute();
InsertionData insertionData = insertionCalculator.getInsertionData(j, empty, bestInsertionData.getInsertionCost());
if (!(insertionData instanceof InsertionData.NoInsertionFound)) {
if (insertionData.getInsertionCost() < bestInsertionData.getInsertionCost()) {
vehicleRoutes.add(empty);
insertJob(j, insertionData, empty);
}
} else {
if (bestRoute != null) insertJob(j, bestInsertionData, bestRoute);
else badJobs.add(j);
}
}
return badJobs;
}
}
public static void main(String[] args) {
Examples.createOutputFolder();
VehicleRoutingProblem.Builder vrpBuilder = VehicleRoutingProblem.Builder.newInstance();
new CordeauReader(vrpBuilder).read("input/p08");
final VehicleRoutingProblem vrp = vrpBuilder.build();
VehicleRoutingAlgorithm vra = createAlgorithm(vrp);
vra.setMaxIterations(2000);
AlgorithmEventsRecorder eventsRecorder = new AlgorithmEventsRecorder(vrp, "output/events.dgs.gz");
eventsRecorder.setRecordingRange(90, 100);
vra.addListener(eventsRecorder);
VehicleRoutingProblemSolution solution = Solutions.bestOf(vra.searchSolutions());
SolutionPrinter.print(vrp, solution, SolutionPrinter.Print.VERBOSE);
// AlgorithmEventsViewer viewer = new AlgorithmEventsViewer();
// viewer.setRuinDelay(3);
// viewer.setRecreationDelay(1);
// viewer.display("output/events.dgs.gz");
}
public static VehicleRoutingAlgorithm createAlgorithm(final VehicleRoutingProblem vrp) {
VehicleFleetManager fleetManager = new FiniteFleetManagerFactory(vrp.getVehicles()).createFleetManager();
StateManager stateManager = new StateManager(vrp);
ConstraintManager constraintManager = new ConstraintManager(vrp, stateManager);
/*
* insertion strategies
*/
//my custom best insertion
MyBestStrategy best = new MyBestStrategy(vrp, fleetManager, stateManager, constraintManager);
//regret insertion
InsertionBuilder iBuilder = new InsertionBuilder(vrp, fleetManager, stateManager, constraintManager);
iBuilder.setInsertionStrategy(InsertionBuilder.Strategy.REGRET);
iBuilder.setFastRegret(true);
RegretInsertionFast regret = (RegretInsertionFast) iBuilder.build();
DefaultScorer scoringFunction = new DefaultScorer(vrp);
scoringFunction.setDepotDistanceParam(0.0);
scoringFunction.setTimeWindowParam(0.0);
regret.setScoringFunction(scoringFunction);
/*
* ruin strategies
*/
RuinStrategy randomRuin = new RandomRuinStrategyFactory(0.5).createStrategy(vrp);
RuinStrategy radialRuin = new RadialRuinStrategyFactory(0.3, new AvgServiceAndShipmentDistance(vrp.getTransportCosts())).createStrategy(vrp);
/*
* objective function
*/
SolutionCostCalculator objectiveFunction = getObjectiveFunction(vrp);
SearchStrategy firstStrategy = new SearchStrategy("firstStrategy", new SelectBest(), new GreedyAcceptance(1), objectiveFunction);
firstStrategy.addModule(new RuinAndRecreateModule("randRuinRegretIns", regret, randomRuin));
SearchStrategy secondStrategy = new SearchStrategy("secondStrategy", new SelectBest(), new GreedyAcceptance(1), objectiveFunction);
secondStrategy.addModule(new RuinAndRecreateModule("radRuinRegretIns", regret, radialRuin));
SearchStrategy thirdStrategy = new SearchStrategy("thirdStrategy", new SelectBest(), new GreedyAcceptance(1), objectiveFunction);
secondStrategy.addModule(new RuinAndRecreateModule("radRuinBestIns", regret, radialRuin));
PrettyAlgorithmBuilder prettyAlgorithmBuilder = PrettyAlgorithmBuilder.newInstance(vrp, fleetManager, stateManager, constraintManager);
final VehicleRoutingAlgorithm vra = prettyAlgorithmBuilder
.withStrategy(firstStrategy, 0.5).withStrategy(secondStrategy, 0.5).withStrategy(thirdStrategy, 0.2)
.addCoreStateAndConstraintStuff()
.constructInitialSolutionWith(regret, objectiveFunction)
.build();
//if you want to switch on/off strategies or adapt their weight within the search, you can do the following
//e.g. from iteration 50 on, switch off first strategy
//switch on again at iteration 90 with slightly higher weight
IterationStartsListener strategyAdaptor = new IterationStartsListener() {
@Override
public void informIterationStarts(int i, VehicleRoutingProblem problem, Collection solutions) {
if (i == 50) {
vra.getSearchStrategyManager().informStrategyWeightChanged("firstStrategy", 0.0);
System.out.println("switched off firstStrategy");
}
if (i == 90) {
vra.getSearchStrategyManager().informStrategyWeightChanged("firstStrategy", 0.7);
System.out.println("switched on firstStrategy again with higher weight");
}
}
};
vra.addListener(strategyAdaptor);
return vra;
}
private static SolutionCostCalculator getObjectiveFunction(final VehicleRoutingProblem vrp) {
return new SolutionCostCalculator() {
@Override
public double getCosts(VehicleRoutingProblemSolution solution) {
SolutionAnalyser analyser = new SolutionAnalyser(vrp, solution, new TransportDistance() {
@Override
public double getDistance(Location from, Location to, double departureTime, Vehicle vehicle) {
return vrp.getTransportCosts().getTransportCost(from, to, 0., null, null);
}
});
return analyser.getVariableTransportCosts() + solution.getUnassignedJobs().size() * 500.;
}
};
}
}
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