    001package net.sf.cpsolver.exam.criteria;
    002
    003import java.util.Set;
    004
    005import net.sf.cpsolver.exam.model.Exam;
    006import net.sf.cpsolver.exam.model.ExamPlacement;
    007import net.sf.cpsolver.exam.model.ExamRoomPlacement;
    008import net.sf.cpsolver.ifs.util.DataProperties;
    009
    010/**
    011 * Room perturbation penalty. I.e., number of assigned rooms different from
    012 * initial. Only applicable when {@link PerturbationPenalty#isMPP()} is true (minimal
    013 * perturbation problem).
    014 * <br><br>
    015 * A weight of room perturbations (i.e., a penalty for
    016 * an assignment of an exam to a room different from the initial one) can be
    017 * set by problem property Exams.RoomPerturbationWeight, or in the input xml
    018 * file, property roomPerturbationWeight).
    019 *
    020 * <br>
    021 *
    022 * @version ExamTT 1.2 (Examination Timetabling)<br>
    023 *          Copyright (C) 2008 - 2012 Tomáš Müller<br>
    024 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    025 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    026 * <br>
    027 *          This library is free software; you can redistribute it and/or modify
    028 *          it under the terms of the GNU Lesser General Public License as
    029 *          published by the Free Software Foundation; either version 3 of the
    030 *          License, or (at your option) any later version. <br>
    031 * <br>
    032 *          This library is distributed in the hope that it will be useful, but
    033 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    034 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    035 *          Lesser General Public License for more details. <br>
    036 * <br>
    037 *          You should have received a copy of the GNU Lesser General Public
    038 *          License along with this library; if not see
    039 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    040 */
    041public class RoomPerturbationPenalty extends PerturbationPenalty {
    042
    043    @Override
    044    public String getWeightName() {
    045        return "Exams.RoomPerturbationWeight";
    046    }
    047
    048    @Override
    049    public String getXmlWeightName() {
    050        return "roomPerturbationWeight";
    051    }
    052
    053    @Override
    054    public double getWeightDefault(DataProperties config) {
    055        return 0.01;
    056    }
    057
    058    @Override
    059    public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) {
    060        if (!isMPP()) return 0;
    061        Exam exam = value.variable();
    062        ExamPlacement initial = exam.getInitialAssignment();
    063        if (initial == null) return 0;
    064        int penalty = 0;
    065        if (value.getRoomPlacements() != null)
    066            for (ExamRoomPlacement rp : value.getRoomPlacements()) {
    067                if (initial.getRoomPlacements() == null || !initial.getRoomPlacements().contains(rp))
    068                    penalty++;
    069            }
    070        return penalty;
    071    }
    072
    073
    074    @Override
    075    public String toString() {
    076        return (isMPP() ? "IRP:" + sDoubleFormat.format(getValue()) : "");
    077    }
    078
    079    @Override
    080    public boolean isPeriodCriterion() { return false; }
    081}