bugfix #128

jsprit-core/src/main/java/jsprit/core/algorithm/acceptor/SchrimpfAcceptance.java

@@ -17,21 +17,13 @@
 package jsprit.core.algorithm.acceptor;
 
 import jsprit.core.algorithm.VehicleRoutingAlgorithm;
-import jsprit.core.algorithm.io.AlgorithmConfig;
-import jsprit.core.algorithm.io.AlgorithmConfigXmlReader;
-import jsprit.core.algorithm.io.VehicleRoutingAlgorithms;
 import jsprit.core.algorithm.listener.AlgorithmStartsListener;
-import jsprit.core.algorithm.listener.IterationEndsListener;
 import jsprit.core.algorithm.listener.IterationStartsListener;
 import jsprit.core.problem.VehicleRoutingProblem;
 import jsprit.core.problem.solution.VehicleRoutingProblemSolution;
-import jsprit.core.util.Resource;
-import jsprit.core.util.Solutions;
-import org.apache.commons.math.stat.descriptive.moment.StandardDeviation;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import java.net.URL;
 import java.util.Collection;
 
 
@@ -81,35 +73,18 @@ public class SchrimpfAcceptance implements SolutionAcceptor, IterationStartsList
 	
 	private final double alpha;
 	
-	private int nOfTotalIterations = 1000;
+	private int maxIterations = 1000;
 	
 	private int currentIteration = 0;
 	
 	private double initialThreshold = 0.0;
 	
-	private int nOfRandomWalks;
-	
 	private final int solutionMemory;
 
-	private boolean determineInitialThreshold = true;
 	
 	public SchrimpfAcceptance(int solutionMemory, double alpha){
 		this.alpha = alpha;
 		this.solutionMemory = solutionMemory;
-		determineInitialThreshold = false;
-		logger.info("initialise " + this);
-	}
-	
-	/**
-	 * @deprecated use <code>new SchrimpfAcceptance(solutionMemory,alpha)</code> instead. if you want to determine ini-threshold with a
-	 * random walk and the algorithm 'randomWalk.xml' use SchrimpfInitialThresholdGenerator.class instead.
-	 */
-	@Deprecated
-	public SchrimpfAcceptance(int solutionMemory, double alpha, int nOfWarmupIterations) {
-		super();
-		this.alpha = alpha;
-		this.nOfRandomWalks = nOfWarmupIterations;
-		this.solutionMemory = solutionMemory;
 		logger.info("initialise " + this);
 	}
 
@@ -141,11 +116,11 @@ public class SchrimpfAcceptance implements SolutionAcceptor, IterationStartsList
 	
 	@Override
 	public String toString() {
-		return "[name=SchrimpfAcceptance][alpha="+alpha+"][warmup=" + nOfRandomWalks + "]";
+		return "[name=SchrimpfAcceptance][alpha="+alpha+"]";
 	}
 	
 	private double getThreshold(int iteration) {
-		double scheduleVariable = (double) iteration / (double) nOfTotalIterations;
+		double scheduleVariable = (double) iteration / (double) maxIterations;
 		return initialThreshold * Math.exp(-1. * Math.log(2) * scheduleVariable / alpha);
 	}
 
@@ -163,53 +138,12 @@ public class SchrimpfAcceptance implements SolutionAcceptor, IterationStartsList
 	 */
 	public void setInitialThreshold(double initialThreshold) {
 		this.initialThreshold = initialThreshold;
-		determineInitialThreshold=false;
 	}
 
 	@Override
 	public void informAlgorithmStarts(VehicleRoutingProblem problem, VehicleRoutingAlgorithm algorithm, Collection<VehicleRoutingProblemSolution> solutions) {
-		if(!determineInitialThreshold){
-			logger.info("skip threshold initialization from here");
-			return;
-		}
         reset();
-		logger.info("---------------------------------------------------------------------");
+        this.maxIterations = algorithm.getMaxIterations();
-		logger.info("prepare schrimpfAcceptanceFunction, i.e. determine initial threshold");
-		logger.info("start random-walk (see randomWalk.xml)");
-		double now = System.currentTimeMillis();
-		this.nOfTotalIterations = algorithm.getMaxIterations();
-
-		/*
-		 * randomWalk to determine standardDev
-		 */
-		final double[] results = new double[nOfRandomWalks];
-
-		URL resource = Resource.getAsURL("randomWalk.xml");
-		AlgorithmConfig algorithmConfig = new AlgorithmConfig();
-		new AlgorithmConfigXmlReader(algorithmConfig).read(resource);
-		VehicleRoutingAlgorithm vra = VehicleRoutingAlgorithms.createAlgorithm(problem, algorithmConfig);
-		vra.setMaxIterations(nOfRandomWalks);
-		vra.getAlgorithmListeners().addListener(new IterationEndsListener() {
-
-			@Override
-			public void informIterationEnds(int iteration, VehicleRoutingProblem problem, Collection<VehicleRoutingProblemSolution> solutions) {
-				double result = Solutions.bestOf(solutions).getCost();
-//				logger.info("result="+result);
-				results[iteration-1] = result;
-			}
-
-		});
-		vra.searchSolutions();
-
-		StandardDeviation dev = new StandardDeviation();
-		double standardDeviation = dev.evaluate(results);
-		initialThreshold = standardDeviation / 2;
-
-		logger.info("warmup done");
-		logger.info("total time: " + ((System.currentTimeMillis()-now)/1000.0) + "s");
-		logger.info("initial threshold: " + initialThreshold);
-		logger.info("---------------------------------------------------------------------");
-
 	}
 
 	private void reset() {

jsprit-core/src/test/java/jsprit/core/algorithm/acceptor/SchrimpfAcceptanceTest.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2014 Stefan Schroeder.
+ * Copyright (C) 2014  Stefan Schroeder
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -8,13 +8,11 @@
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
- * 
- * Contributors:
- *     Stefan Schroeder - initial API and implementation
  ******************************************************************************/
 package jsprit.core.algorithm.acceptor;
 
@@ -44,7 +42,7 @@ public class SchrimpfAcceptanceTest {
 	@SuppressWarnings("deprecation")
 	@Before
 	public void setup() {
-		schrimpfAcceptance = new SchrimpfAcceptance(1, 0.3, 100);
+		schrimpfAcceptance = new SchrimpfAcceptance(1, 0.3);
 		// we skip the warmup, but still want to test that the initialThreshold is set
 		schrimpfAcceptance.setInitialThreshold(0.0);
 		// create empty memory with an initial capacity of 1

jsprit-examples/src/main/java/jsprit/examples/SolomonR101Example.java

@@ -62,7 +62,8 @@ public class SolomonR101Example {
 		 * The algorithm can be defined and configured in an xml-file.
 		 */
 //		VehicleRoutingAlgorithm vra = new SchrimpfFactory().createAlgorithm(vrp);
-		VehicleRoutingAlgorithm vra = VehicleRoutingAlgorithms.readAndCreateAlgorithm(vrp, "input/algorithmConfig_solomon.xml");
+		VehicleRoutingAlgorithm vra = VehicleRoutingAlgorithms.readAndCreateAlgorithm(vrp, "input/algorithmConfig.xml");
+        vra.setMaxIterations(100);
 //		vra.setPrematureBreak(100);
 //		vra.getAlgorithmListeners().addListener(new AlgorithmSearchProgressChartListener("output/sol_progress.png"));
 		/*