    001package net.sf.cpsolver.exam.neighbours;
    002
    003import java.text.DecimalFormat;
    004
    005import org.apache.log4j.Logger;
    006
    007import net.sf.cpsolver.exam.model.Exam;
    008import net.sf.cpsolver.exam.model.ExamModel;
    009import net.sf.cpsolver.exam.model.ExamPlacement;
    010import 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 Tomáš Müller<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 */
    037public 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}