    001package org.cpsolver.exam.criteria;
    002
    003import java.util.Map;
    004import java.util.Set;
    005
    006import org.cpsolver.exam.model.Exam;
    007import org.cpsolver.exam.model.ExamModel;
    008import org.cpsolver.exam.model.ExamPlacement;
    009import org.cpsolver.exam.model.ExamRoom;
    010import org.cpsolver.exam.model.ExamRoomPlacement;
    011import org.cpsolver.ifs.assignment.Assignment;
    012import org.cpsolver.ifs.model.Model;
    013import org.cpsolver.ifs.util.DataProperties;
    014
    015
    016/**
    017 *
    018 * Cost for using room(s) that are too big. I.e., a difference between total room size
    019 * (computed using either {@link ExamRoom#getSize()} or {@link ExamRoom#getAltSize()} based
    020 * on {@link Exam#hasAltSeating()}) and the number of students {@link Exam#getSize()}.
    021 * <br><br>
    022 * A weight for room size penalty can be set by problem
    023 * property Exams.RoomSizeWeight, or in the input xml file, property
    024 * roomSizeWeight).
    025 * <br><br>
    026 * The difference function can be made polynomial by using Exams.RoomSizeFactor parameter
    027 * (defaults to 1.0). The value of this criteria is then cubed by the power of this room
    028 * size factor. This is to be able to favor a room swap between two exams at the same period,
    029 * in which a smaller exam takes a smaller room. To do this, set Exams.RoomSizeFactor to
    030 * a number bigger than one that is close to one (e.g., 1.05).
    031 *
    032 * <br>
    033 *
    034 * @version ExamTT 1.3 (Examination Timetabling)<br>
    035 *          Copyright (C) 2008 - 2014 Tomáš Müller<br>
    036 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    037 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    038 * <br>
    039 *          This library is free software; you can redistribute it and/or modify
    040 *          it under the terms of the GNU Lesser General Public License as
    041 *          published by the Free Software Foundation; either version 3 of the
    042 *          License, or (at your option) any later version. <br>
    043 * <br>
    044 *          This library is distributed in the hope that it will be useful, but
    045 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    046 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    047 *          Lesser General Public License for more details. <br>
    048 * <br>
    049 *          You should have received a copy of the GNU Lesser General Public
    050 *          License along with this library; if not see
    051 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    052 */
    053public class RoomSizePenalty extends ExamCriterion {
    054    private double iRoomSizeFactor = 1.0;
    055
    056    @Override
    057    public void configure(DataProperties properties) {
    058        super.configure(properties);
    059        iRoomSizeFactor = properties.getPropertyDouble("Exams.RoomSizeFactor", 1.0);
    060    }
    061
    062    @Override
    063    public void setModel(Model<Exam, ExamPlacement> model) {
    064        super.setModel(model);
    065        iRoomSizeFactor = ((ExamModel)model).getProperties().getPropertyDouble("Exams.RoomSizeFactor", 1.0);
    066    }
    067
    068    @Override
    069    public String getWeightName() {
    070        return "Exams.RoomSizeWeight";
    071    }
    072
    073    @Override
    074    public String getXmlWeightName() {
    075        return "roomSizeWeight";
    076    }
    077
    078    @Override
    079    public double getWeightDefault(DataProperties config) {
    080        return 0.0001;
    081    }
    082
    083    @Override
    084    public void getXmlParameters(Map<String, String> params) {
    085        params.put(getXmlWeightName(), String.valueOf(getWeight()));
    086        params.put("roomSizeFactor", String.valueOf(iRoomSizeFactor));
    087    }
    088
    089    @Override
    090    public void setXmlParameters(Map<String, String> params) {
    091        try {
    092            setWeight(Double.valueOf(params.get(getXmlWeightName())));
    093        } catch (NumberFormatException e) {} catch (NullPointerException e) {}
    094        try {
    095            iRoomSizeFactor = Double.valueOf(params.get("roomSizeFactor"));
    096        } catch (NumberFormatException e) {} catch (NullPointerException e) {}
    097    }
    098
    099    @Override
    100    public double getValue(Assignment<Exam, ExamPlacement> assignment, ExamPlacement value, Set<ExamPlacement> conflicts) {
    101        Exam exam = value.variable();
    102        int size = 0;
    103        if (value.getRoomPlacements() != null)
    104            for (ExamRoomPlacement r : value.getRoomPlacements()) {
    105                size += r.getSize(exam.hasAltSeating());
    106            }
    107        int diff = size - exam.getSize();
    108        return (diff < 0 ? 0 : Math.pow(diff, iRoomSizeFactor));
    109    }
    110
    111    @Override
    112    public void getInfo(Assignment<Exam, ExamPlacement> assignment, Map<String, String> info) {
    113        if (getValue(assignment) != 0.0) {
    114            info.put(getName(), sDoubleFormat.format(getValue(assignment) / assignment.nrAssignedVariables()));
    115        }
    116    }
    117
    118    @Override
    119    public String toString(Assignment<Exam, ExamPlacement> assignment) {
    120        return "RSz:" + sDoubleFormat.format(getValue(assignment) / assignment.nrAssignedVariables());
    121    }
    122
    123    @Override
    124    public boolean isPeriodCriterion() { return false; }
    125}