    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 * @version ExamTT 1.3 (Examination Timetabling)<br>
    025 *          Copyright (C) 2008 - 2014 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 RoomPerturbationPenalty extends PerturbationPenalty {
    044
    045    @Override
    046    public String getWeightName() {
    047        return "Exams.RoomPerturbationWeight";
    048    }
    049
    050    @Override
    051    public String getXmlWeightName() {
    052        return "roomPerturbationWeight";
    053    }
    054
    055    @Override
    056    public double getWeightDefault(DataProperties config) {
    057        return 0.01;
    058    }
    059
    060    @Override
    061    public double getValue(Assignment<Exam, ExamPlacement> assignment, ExamPlacement value, Set<ExamPlacement> conflicts) {
    062        if (!isMPP()) return 0;
    063        Exam exam = value.variable();
    064        ExamPlacement initial = exam.getInitialAssignment();
    065        if (initial == null) return 0;
    066        int penalty = 0;
    067        if (value.getRoomPlacements() != null)
    068            for (ExamRoomPlacement rp : value.getRoomPlacements()) {
    069                if (initial.getRoomPlacements() == null || !initial.getRoomPlacements().contains(rp))
    070                    penalty++;
    071            }
    072        return penalty;
    073    }
    074
    075
    076    @Override
    077    public String toString(Assignment<Exam, ExamPlacement> assignment) {
    078        return (isMPP() ? "IRP:" + sDoubleFormat.format(getValue(assignment)) : "");
    079    }
    080
    081    @Override
    082    public boolean isPeriodCriterion() { return false; }
    083}