    001package net.sf.cpsolver.exam.criteria;
    002
    003import java.util.Set;
    004
    005import net.sf.cpsolver.exam.criteria.additional.DistributionViolation;
    006import net.sf.cpsolver.exam.model.Exam;
    007import net.sf.cpsolver.exam.model.ExamDistributionConstraint;
    008import net.sf.cpsolver.exam.model.ExamModel;
    009import net.sf.cpsolver.exam.model.ExamPlacement;
    010import net.sf.cpsolver.ifs.solver.Solver;
    011import net.sf.cpsolver.ifs.util.DataProperties;
    012
    013/**
    014 * Distribution penalty. I.e., sum weights of violated distribution
    015 * constraints.
    016 * <br><br>
    017 * A weight of violated distribution soft constraints (see
    018 * {@link ExamDistributionConstraint}) can be set by problem property
    019 * Exams.RoomDistributionWeight, or in the input xml file, property
    020 * roomDistributionWeight.
    021 *
    022 * <br>
    023 *
    024 * @version ExamTT 1.2 (Examination Timetabling)<br>
    025 *          Copyright (C) 2008 - 2012 Tomáš Müller<br>
    026 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    027 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    028 * <br>
    029 *          This library is free software; you can redistribute it and/or modify
    030 *          it under the terms of the GNU Lesser General Public License as
    031 *          published by the Free Software Foundation; either version 3 of the
    032 *          License, or (at your option) any later version. <br>
    033 * <br>
    034 *          This library is distributed in the hope that it will be useful, but
    035 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    036 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    037 *          Lesser General Public License for more details. <br>
    038 * <br>
    039 *          You should have received a copy of the GNU Lesser General Public
    040 *          License along with this library; if not see
    041 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    042 */
    043public class DistributionPenalty extends ExamCriterion {
    044    protected Integer iSoftDistributions = null;
    045
    046    public DistributionPenalty() {
    047        iValueUpdateType = ValueUpdateType.NoUpdate;
    048    }
    049
    050
    051    @Override
    052    public boolean init(Solver<Exam, ExamPlacement> solver) {
    053        if (super.init(solver)) {
    054            iSoftDistributions = solver.getProperties().getPropertyInteger("Exam.SoftDistributions", null);
    055            if (iSoftDistributions != null) {
    056                DistributionViolation dv = new DistributionViolation();
    057                getModel().addCriterion(dv);
    058                return dv.init(solver);
    059            }
    060        }
    061        return true;
    062    }
    063
    064    @Override
    065    public String getWeightName() {
    066        return "Exams.DistributionWeight";
    067    }
    068
    069    @Override
    070    public String getXmlWeightName() {
    071        return "distributionWeight";
    072    }
    073
    074    @Override
    075    public double getWeightDefault(DataProperties config) {
    076        return 1.0;
    077    }
    078
    079    @Override
    080    public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) {
    081        int penalty = 0;
    082        for (ExamDistributionConstraint dc : value.variable().getDistributionConstraints()) {
    083            if (dc.isHard() || (iSoftDistributions != null && iSoftDistributions == dc.getWeight()))
    084                continue;
    085            boolean sat = dc.isSatisfied(value);
    086            if (sat != dc.isSatisfied())
    087                penalty += (sat ? -dc.getWeight() : dc.getWeight());
    088        }
    089        return penalty;
    090    }
    091
    092    @Override
    093    public boolean isRoomCriterion() { return true; }
    094
    095    /**
    096     * Room related distribution penalty, i.e., sum weights of violated
    097     * distribution constraints
    098     */
    099    @Override
    100    public double getRoomValue(ExamPlacement value) {
    101        int penalty = 0;
    102        for (ExamDistributionConstraint dc : value.variable().getDistributionConstraints()) {
    103            if (dc.isHard() || (iSoftDistributions != null && iSoftDistributions == dc.getWeight()) || !dc.isRoomRelated())
    104                continue;
    105            boolean sat = dc.isSatisfied(value);
    106            if (sat != dc.isSatisfied())
    107                penalty += (sat ? -dc.getWeight() : dc.getWeight());
    108        }
    109        return penalty;
    110    }
    111
    112
    113    @Override
    114    public boolean isPeriodCriterion() { return true; }
    115
    116    @Override
    117    public void inc(double value) {
    118        if (iSoftDistributions != null && iSoftDistributions == value) {
    119            getModel().getCriterion(DistributionViolation.class).inc(1.0);
    120        } else if (iSoftDistributions != null && iSoftDistributions == -value) {
    121            getModel().getCriterion(DistributionViolation.class).inc(-1.0);
    122        } else {
    123            super.inc(value);
    124        }
    125    }
    126
    127    /**
    128     * Period related distribution penalty, i.e., sum weights of violated
    129     * distribution constraints
    130     */
    131    @Override
    132    public double getPeriodValue(ExamPlacement value) {
    133        int penalty = 0;
    134        for (ExamDistributionConstraint dc : value.variable().getDistributionConstraints()) {
    135            if (dc.isHard() || (iSoftDistributions != null && iSoftDistributions == dc.getWeight()) || !dc.isPeriodRelated())
    136                continue;
    137            boolean sat = dc.isSatisfied(value);
    138            if (sat != dc.isSatisfied())
    139                penalty += (sat ? -dc.getWeight() : dc.getWeight());
    140        }
    141        return penalty;
    142    }
    143
    144    @Override
    145    protected double[] computeBounds() {
    146        double[] bounds = new double[] { 0.0, 0.0 };
    147        for (ExamDistributionConstraint dc : ((ExamModel)getModel()).getDistributionConstraints()) {
    148            if (dc.isHard() || (iSoftDistributions != null && iSoftDistributions == dc.getWeight()))
    149                continue;
    150            bounds[1] += dc.getWeight();
    151        }
    152        return bounds;
    153    }
    154
    155    @Override
    156    public String toString() {
    157        return (getValue() <= 0.0 ? "" : "DP:" + sDoubleFormat.format(getValue()));
    158    }
    159}