001 package net.sf.cpsolver.exam.neighbours;
002
003 import java.text.DecimalFormat;
004
005 import org.apache.log4j.Logger;
006
007 import net.sf.cpsolver.exam.model.Exam;
008 import net.sf.cpsolver.exam.model.ExamModel;
009 import net.sf.cpsolver.exam.model.ExamPlacement;
010 import net.sf.cpsolver.ifs.model.SimpleNeighbour;
011
012 /**
013 * Extension of {@link SimpleNeighbour}. The only difference is that the value (
014 * {@link SimpleNeighbour#value()}) is decreased by 1000 if the selected
015 * variable has no current assignment. <br>
016 * <br>
017 *
018 * @version ExamTT 1.2 (Examination Timetabling)<br>
019 * Copyright (C) 2008 - 2010 Tomas Muller<br>
020 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
021 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
022 * <br>
023 * This library is free software; you can redistribute it and/or modify
024 * it under the terms of the GNU Lesser General Public License as
025 * published by the Free Software Foundation; either version 3 of the
026 * License, or (at your option) any later version. <br>
027 * <br>
028 * This library is distributed in the hope that it will be useful, but
029 * WITHOUT ANY WARRANTY; without even the implied warranty of
030 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
031 * Lesser General Public License for more details. <br>
032 * <br>
033 * You should have received a copy of the GNU Lesser General Public
034 * License along with this library; if not see
035 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
036 */
037 public class ExamSimpleNeighbour extends SimpleNeighbour<Exam, ExamPlacement> {
038 private static Logger sLog = Logger.getLogger(ExamSimpleNeighbour.class);
039 private static boolean sCheck = false;
040 private double iValue = 0;
041 private double iDx;
042
043 public ExamSimpleNeighbour(ExamPlacement placement) {
044 super(placement.variable(), placement);
045 iValue = placement.toDouble();
046 if (placement.variable().getAssignment() != null)
047 iValue -= placement.variable().getAssignment().toDouble();
048 else
049 iValue -= 1000;
050 if (sCheck) {
051 iDx = placement.toDouble();
052 if (placement.variable().getAssignment() != null)
053 iDx -= placement.variable().getAssignment().toDouble();
054 }
055 }
056
057 @Override
058 public void assign(long iteration) {
059 if (sCheck) {
060 double beforeVal = getVariable().getModel().getTotalValue();
061 double[] beforeValM = ((ExamModel) getVariable().getModel()).getTotalMultiValue();
062 String n = toString();
063 getVariable().assign(iteration, getValue());
064 double afterVal = getVariable().getModel().getTotalValue();
065 double[] afterValM = ((ExamModel) getVariable().getModel()).getTotalMultiValue();
066 /*
067 * int before = getVariable().getModel().nrUnassignedVariables();
068 * int after = getVariable().getModel().nrUnassignedVariables(); if
069 * (after>before) {
070 * sLog.error("-- assignment mischmatch (delta:"+(after
071 * -before)+")"); sLog.error(" -- neighbour: "+n); }
072 */
073 if (Math.abs(afterVal - beforeVal - iDx) >= 0.0000001) {
074 sLog.error("-- value mischmatch (delta:" + (afterVal - beforeVal) + ", value:" + iDx + ")");
075 sLog.error(" -- neighbour: " + n);
076 sLog.error(" -- solution: " + toString(afterValM, beforeValM));
077 }
078 } else {
079 getVariable().assign(iteration, getValue());
080 }
081 }
082
083 protected static String toString(double[] x) {
084 DecimalFormat df = new DecimalFormat("0.00");
085 StringBuffer s = new StringBuffer();
086 for (int i = 0; i < x.length; i++) {
087 if (i > 0)
088 s.append(",");
089 s.append(df.format(x[i]));
090 }
091 return "[" + s.toString() + "]";
092 }
093
094 protected static String toString(double[] x, double[] y) {
095 DecimalFormat df = new DecimalFormat("0.00");
096 StringBuffer s = new StringBuffer();
097 for (int i = 0; i < x.length; i++) {
098 if (i > 0)
099 s.append(",");
100 s.append(df.format(x[i] - y[i]));
101 }
102 return "[" + s.toString() + "]";
103 }
104
105 @Override
106 public String toString() {
107 return getVariable().getAssignment() + " -> " + getValue().toString() + " / " + " (value:" + value() + ")";
108 }
109
110 @Override
111 public double value() {
112 return iValue;
113 }
114 }