1
0
Fork 0
mirror of https://github.com/graphhopper/jsprit.git synced 2020-01-24 07:45:05 +01:00

refine string removal

This commit is contained in:
oblonski 2017-01-18 19:43:52 +01:00
parent 142c3beff6
commit 25fe083809
No known key found for this signature in database
GPG key ID: 179DE487285680D1
8 changed files with 960 additions and 264 deletions

View file

@ -82,7 +82,9 @@ public class Jsprit {
WORST_BEST("worst_best"),
WORST_REGRET("worst_regret"),
CLUSTER_BEST("cluster_best"),
CLUSTER_REGRET("cluster_regret");
CLUSTER_REGRET("cluster_regret"),
STRING_BEST("string_best"),
STRING_REGRET("string_regret");
String strategyName;
@ -178,6 +180,10 @@ public class Jsprit {
defaults.put(Strategy.RADIAL_REGRET.toString(), ".5");
defaults.put(Strategy.RANDOM_BEST.toString(), ".5");
defaults.put(Strategy.RANDOM_REGRET.toString(), ".5");
defaults.put(Strategy.STRING_BEST.toString(), ".5");
defaults.put(Strategy.STRING_REGRET.toString(), ".5");
defaults.put(Strategy.WORST_BEST.toString(), "0.");
defaults.put(Strategy.WORST_REGRET.toString(), "1.");
defaults.put(Strategy.CLUSTER_BEST.toString(), "0.");
@ -472,6 +478,9 @@ public class Jsprit {
random)
);
final RuinString stringRuin = new RuinString(vrp, jobNeighborhoods);
stringRuin.setRandom(random);
AbstractInsertionStrategy regret;
final ScoringFunction scorer;
@ -592,6 +601,11 @@ public class Jsprit {
final SearchStrategy clusters_best = new SearchStrategy(Strategy.CLUSTER_BEST.toString(), new SelectBest(), acceptor, objectiveFunction);
clusters_best.addModule(new RuinAndRecreateModule(Strategy.CLUSTER_BEST.toString(), best, clusters));
SearchStrategy stringRegret = new SearchStrategy(Strategy.STRING_REGRET.toString(), new SelectBest(), acceptor, objectiveFunction);
stringRegret.addModule(new RuinAndRecreateModule(Strategy.STRING_REGRET.toString(), regret, stringRuin));
SearchStrategy stringBest = new SearchStrategy(Strategy.STRING_BEST.toString(), new SelectBest(), acceptor, objectiveFunction);
stringBest.addModule(new RuinAndRecreateModule(Strategy.STRING_BEST.toString(), best, stringRuin));
PrettyAlgorithmBuilder prettyBuilder = PrettyAlgorithmBuilder.newInstance(vrp, fm, stateManager, constraintManager);
prettyBuilder.setRandom(random);
@ -605,7 +619,10 @@ public class Jsprit {
.withStrategy(worst_best, toDouble(getProperty(Strategy.WORST_BEST.toString())))
.withStrategy(worst_regret, toDouble(getProperty(Strategy.WORST_REGRET.toString())))
.withStrategy(clusters_regret, toDouble(getProperty(Strategy.CLUSTER_REGRET.toString())))
.withStrategy(clusters_best, toDouble(getProperty(Strategy.CLUSTER_BEST.toString())));
.withStrategy(clusters_best, toDouble(getProperty(Strategy.CLUSTER_BEST.toString())))
.withStrategy(stringBest, toDouble(getProperty(Strategy.STRING_BEST.toString())))
.withStrategy(stringRegret, toDouble(getProperty(Strategy.STRING_REGRET.toString())));
if (getProperty(Parameter.CONSTRUCTION.toString()).equals(Construction.BEST_INSERTION.toString())) {
prettyBuilder.constructInitialSolutionWith(best, objectiveFunction);
} else {

View file

@ -0,0 +1,231 @@
/*
* Licensed to GraphHopper GmbH under one or more contributor
* license agreements. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*
* GraphHopper GmbH licenses this file to you under the Apache License,
* Version 2.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.graphhopper.jsprit.core.algorithm.ruin;
import com.graphhopper.jsprit.core.algorithm.ruin.distance.JobDistance;
import com.graphhopper.jsprit.core.problem.AbstractActivity;
import com.graphhopper.jsprit.core.problem.VehicleRoutingProblem;
import com.graphhopper.jsprit.core.problem.job.Job;
import com.graphhopper.jsprit.core.problem.solution.route.VehicleRoute;
import com.graphhopper.jsprit.core.problem.solution.route.activity.TourActivity;
import com.graphhopper.jsprit.core.util.RandomUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.*;
/**
* RuinStrategy that ruins the neighborhood of a randomly selected job. The size and the structure of the neighborhood is defined by
* the share of jobs to be removed and the distance between jobs (where distance not necessarily mean Euclidean distance but an arbitrary
* measure).
*
* @author stefan
*/
public final class RuinString extends AbstractRuinStrategy {
private Logger logger = LoggerFactory.getLogger(RuinString.class);
private VehicleRoutingProblem vrp;
private JobNeighborhoods jobNeighborhoods;
private int Kmin = 1;
private int Kmax = 6;
private int Lmin = 1;
private int Lmax = 40;
/**
* Constructs RuinRadial.
*
* @param vrp
* @param jobDistance i.e. a measure to define the distance between two jobs and whether they are located close or distant to eachother
* @param Kmin
* @param Kmax
* @param Lmin
* @param Lmax
*/
public RuinString(VehicleRoutingProblem vrp, JobDistance jobDistance, int Kmin, int Kmax, int Lmin, int Lmax) {
super(vrp);
this.vrp = vrp;
JobNeighborhoodsImplWithCapRestriction jobNeighborhoodsImpl = new JobNeighborhoodsImplWithCapRestriction(vrp, jobDistance, Kmax * Lmax);
jobNeighborhoodsImpl.initialise();
jobNeighborhoods = jobNeighborhoodsImpl;
this.Kmin = Kmin;
this.Kmax = Kmax;
this.Lmin = Lmin;
this.Lmax = Lmax;
logger.debug("initialise {}", this);
}
public RuinString(VehicleRoutingProblem vrp, JobDistance jobDistance) {
super(vrp);
this.vrp = vrp;
JobNeighborhoodsImplWithCapRestriction jobNeighborhoodsImpl = new JobNeighborhoodsImplWithCapRestriction(vrp, jobDistance, Kmax * Lmax);
jobNeighborhoodsImpl.initialise();
jobNeighborhoods = jobNeighborhoodsImpl;
logger.debug("initialise {}", this);
}
public RuinString(VehicleRoutingProblem vrp, JobNeighborhoods jobNeighborhoods) {
super(vrp);
this.vrp = vrp;
this.jobNeighborhoods = jobNeighborhoods;
logger.debug("initialise {}", this);
}
@Override
public String toString() {
return "[name=splitRuin]";
}
/**
* Ruins the collection of vehicleRoutes, i.e. removes a share of jobs. First, it selects a job randomly. Second, it identifies its neighborhood. And finally, it removes
* the neighborhood plus the randomly selected job from the number of vehicleRoutes. All removed jobs are then returned as a collection.
*/
@Override
public Collection<Job> ruinRoutes(Collection<VehicleRoute> vehicleRoutes) {
if (vehicleRoutes.isEmpty() || vrp.getJobs().isEmpty()) {
return Collections.emptyList();
}
int noStrings = Kmin + random.nextInt((Kmax - Kmin));
noStrings = Math.min(noStrings, vehicleRoutes.size());
Set<Job> unassignedJobs = new HashSet<>();
Set<VehicleRoute> ruinedRoutes = new HashSet<>();
Job prevJob = RandomUtils.nextJob(vrp.getJobs().values(), random);
Iterator<Job> neighborhoodIterator = jobNeighborhoods.getNearestNeighborsIterator(Kmax * Lmax, prevJob);
while (neighborhoodIterator.hasNext() && ruinedRoutes.size() <= noStrings) {
if (!unassignedJobs.contains(prevJob)) {
VehicleRoute route = getRouteOf(prevJob, vehicleRoutes);
if (route != null && !ruinedRoutes.contains(route)) {
if (random.nextDouble() < .5) {
ruinRouteWithStringRuin(route, prevJob, unassignedJobs);
} else {
ruinRouteWithSplitStringRuin(route, prevJob, unassignedJobs);
}
ruinedRoutes.add(route);
}
}
prevJob = neighborhoodIterator.next();
}
return unassignedJobs;
}
private VehicleRoute getRouteOf(Job job, Collection<VehicleRoute> vehicleRoutes) {
for (VehicleRoute route : vehicleRoutes) {
if (route.getTourActivities().servesJob(job)) return route;
}
return null;
}
private void ruinRouteWithSplitStringRuin(VehicleRoute seedRoute, Job prevJob, Set<Job> unassignedJobs) {
int noActivities = seedRoute.getActivities().size();
int stringLength = Lmin + random.nextInt(Lmax - Lmin);
stringLength = Math.min(stringLength, seedRoute.getActivities().size());
int preservedSubstringLength = StringUtil.determineSubstringLength(stringLength, noActivities, random);
List<AbstractActivity> acts = vrp.getActivities(prevJob);
AbstractActivity randomSeedAct = RandomUtils.nextItem(acts, random);
int seedIndex = 0;
int index = 0;
for (TourActivity act : seedRoute.getActivities()) {
if (act.getIndex() == randomSeedAct.getIndex()) {
seedIndex = index;
break;
}
index++;
}
int totalStringLength = stringLength + preservedSubstringLength;
List<Integer> stringBounds = StringUtil.getLowerBoundsOfAllStrings(totalStringLength, seedIndex, noActivities);
if (stringBounds.isEmpty()) return;
int lowerBound = RandomUtils.nextItem(stringBounds, random);
List<Job> jobs2Remove = new ArrayList<>();
int startIndexOfPreservedSubstring = random.nextInt(stringLength);
int position = 0;
int noStringsInPreservedSubstring = 0;
boolean isPreservedSubstring = false;
for (int i = lowerBound; i < (lowerBound + totalStringLength); i++) {
if (position == startIndexOfPreservedSubstring) {
isPreservedSubstring = true;
}
if (noStringsInPreservedSubstring >= preservedSubstringLength) {
isPreservedSubstring = false;
}
if (!isPreservedSubstring) {
TourActivity act = seedRoute.getActivities().get(i);
if (act instanceof TourActivity.JobActivity) {
Job job = ((TourActivity.JobActivity) act).getJob();
if (vrp.getJobs().containsKey(job.getId())) {
jobs2Remove.add(job);
}
}
} else noStringsInPreservedSubstring++;
position++;
}
for (Job job : jobs2Remove) {
removeJob(job, seedRoute);
unassignedJobs.add(job);
}
}
private void ruinRouteWithStringRuin(VehicleRoute seedRoute, Job prevJob, Set<Job> unassignedJobs) {
int stringLength = Lmin + random.nextInt(Lmax - Lmin);
stringLength = Math.min(stringLength, seedRoute.getActivities().size());
List<AbstractActivity> acts = vrp.getActivities(prevJob);
AbstractActivity randomSeedAct = RandomUtils.nextItem(acts, random);
int seedIndex = 0;
int noActivities = seedRoute.getActivities().size();
int index = 0;
for (TourActivity act : seedRoute.getActivities()) {
if (act.getIndex() == randomSeedAct.getIndex()) {
seedIndex = index;
break;
}
index++;
}
List<Integer> stringBounds = StringUtil.getLowerBoundsOfAllStrings(stringLength, seedIndex, noActivities);
if (stringBounds.isEmpty()) return;
int lowerBound = RandomUtils.nextItem(stringBounds, random);
List<Job> jobs2Remove = new ArrayList<>();
for (int i = lowerBound; i < (lowerBound + stringLength); i++) {
TourActivity act = seedRoute.getActivities().get(i);
if (act instanceof TourActivity.JobActivity) {
Job job = ((TourActivity.JobActivity) act).getJob();
if (vrp.getJobs().containsKey(job.getId())) {
jobs2Remove.add(job);
}
}
}
for (Job job : jobs2Remove) {
removeJob(job, seedRoute);
unassignedJobs.add(job);
}
}
}

View file

@ -0,0 +1,52 @@
/*
* Licensed to GraphHopper GmbH under one or more contributor
* license agreements. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*
* GraphHopper GmbH licenses this file to you under the Apache License,
* Version 2.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.graphhopper.jsprit.core.algorithm.ruin;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
/**
* Created by schroeder on 13/01/17.
*/
class StringUtil {
static List<Integer> getLowerBoundsOfAllStrings(int length, int seedIndex, int routeLength) {
List<Integer> lowerBounds = new ArrayList<>();
for (int i = 1; i <= length; i++) {
int lower = seedIndex - (length - i);
int upper = seedIndex + (i - 1);
if (lower >= 0 && upper < routeLength) {
lowerBounds.add(lower);
}
}
return lowerBounds;
}
static int determineSubstringLength(int baseLength, int routeLength, Random random) {
if (baseLength == routeLength) return 0;
int substringLength = 1;
while (baseLength + substringLength < routeLength) {
if (random.nextDouble() < 0.01) {
return substringLength;
} else substringLength++;
}
return substringLength;
}
}

View file

@ -0,0 +1,87 @@
/*
* Licensed to GraphHopper GmbH under one or more contributor
* license agreements. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*
* GraphHopper GmbH licenses this file to you under the Apache License,
* Version 2.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.graphhopper.jsprit.core.algorithm.ruin;
import org.junit.Assert;
import org.junit.Test;
import java.util.List;
/**
* Created by schroeder on 13/01/17.
*/
public class StringUtilTest {
@Test
public void test() {
int stringLength = 4;
int seedIndex = 4;
int noActivities = 10;
List<Integer> bounds = StringUtil.getLowerBoundsOfAllStrings(stringLength, seedIndex, noActivities);
Assert.assertEquals(4, bounds.size());
Assert.assertEquals(1, (int) bounds.get(0));
Assert.assertEquals(2, (int) bounds.get(1));
Assert.assertEquals(3, (int) bounds.get(2));
Assert.assertEquals(4, (int) bounds.get(3));
}
@Test
public void test2() {
int stringLength = 4;
int seedIndex = 2;
int noActivities = 10;
List<Integer> bounds = StringUtil.getLowerBoundsOfAllStrings(stringLength, seedIndex, noActivities);
Assert.assertEquals(3, bounds.size());
Assert.assertEquals(0, (int) bounds.get(0));
Assert.assertEquals(1, (int) bounds.get(1));
Assert.assertEquals(2, (int) bounds.get(2));
}
@Test
public void test3() {
int stringLength = 4;
int seedIndex = 0;
int noActivities = 10;
List<Integer> bounds = StringUtil.getLowerBoundsOfAllStrings(stringLength, seedIndex, noActivities);
Assert.assertEquals(1, bounds.size());
Assert.assertEquals(0, (int) bounds.get(0));
}
@Test
public void test4() {
int stringLength = 4;
int seedIndex = 9;
int noActivities = 10;
List<Integer> bounds = StringUtil.getLowerBoundsOfAllStrings(stringLength, seedIndex, noActivities);
Assert.assertEquals(1, bounds.size());
Assert.assertEquals(6, (int) bounds.get(0));
}
@Test
public void test5() {
int stringLength = 4;
int seedIndex = 8;
int noActivities = 10;
List<Integer> bounds = StringUtil.getLowerBoundsOfAllStrings(stringLength, seedIndex, noActivities);
Assert.assertEquals(2, bounds.size());
Assert.assertEquals(5, (int) bounds.get(0));
Assert.assertEquals(6, (int) bounds.get(1));
}
}