    001package org.cpsolver.exam.criteria;
    002
    003import java.util.Set;
    004
    005import org.cpsolver.exam.model.Exam;
    006import org.cpsolver.exam.model.ExamPlacement;
    007import org.cpsolver.exam.model.ExamRoomPlacement;
    008import org.cpsolver.ifs.assignment.Assignment;
    009import org.cpsolver.ifs.util.DataProperties;
    010
    011
    012/**
    013 * Room perturbation penalty. I.e., number of assigned rooms different from
    014 * initial. Only applicable when {@link PerturbationPenalty#isMPP()} is true (minimal
    015 * perturbation problem).
    016 * <br><br>
    017 * A weight of room perturbations (i.e., a penalty for
    018 * an assignment of an exam to a room different from the initial one) can be
    019 * set by problem property Exams.RoomPerturbationWeight, or in the input xml
    020 * file, property roomPerturbationWeight).
    021 *
    022 * <br>
    023 *
    024 * @author  Tomáš Müller
    025 * @version ExamTT 1.3 (Examination Timetabling)<br>
    026 *          Copyright (C) 2008 - 2014 Tomáš Müller<br>
    027 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    028 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    029 * <br>
    030 *          This library is free software; you can redistribute it and/or modify
    031 *          it under the terms of the GNU Lesser General Public License as
    032 *          published by the Free Software Foundation; either version 3 of the
    033 *          License, or (at your option) any later version. <br>
    034 * <br>
    035 *          This library is distributed in the hope that it will be useful, but
    036 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    037 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    038 *          Lesser General Public License for more details. <br>
    039 * <br>
    040 *          You should have received a copy of the GNU Lesser General Public
    041 *          License along with this library; if not see
    042 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    043 */
    044public class RoomPerturbationPenalty extends PerturbationPenalty {
    045
    046    @Override
    047    public String getWeightName() {
    048        return "Exams.RoomPerturbationWeight";
    049    }
    050
    051    @Override
    052    public String getXmlWeightName() {
    053        return "roomPerturbationWeight";
    054    }
    055
    056    @Override
    057    public double getWeightDefault(DataProperties config) {
    058        return 0.01;
    059    }
    060
    061    @Override
    062    public double getValue(Assignment<Exam, ExamPlacement> assignment, ExamPlacement value, Set<ExamPlacement> conflicts) {
    063        if (!isMPP()) return 0;
    064        Exam exam = value.variable();
    065        ExamPlacement initial = exam.getInitialAssignment();
    066        if (initial == null) return 0;
    067        int penalty = 0;
    068        if (value.getRoomPlacements() != null)
    069            for (ExamRoomPlacement rp : value.getRoomPlacements()) {
    070                if (initial.getRoomPlacements() == null || !initial.getRoomPlacements().contains(rp))
    071                    penalty++;
    072            }
    073        return penalty;
    074    }
    075
    076
    077    @Override
    078    public String toString(Assignment<Exam, ExamPlacement> assignment) {
    079        return (isMPP() ? "IRP:" + sDoubleFormat.format(getValue(assignment)) : "");
    080    }
    081
    082    @Override
    083    public boolean isPeriodCriterion() { return false; }
    084}