    001package org.cpsolver.coursett.criteria.additional;
    002
    003import java.util.Map;
    004import java.util.Set;
    005
    006import org.cpsolver.coursett.criteria.TimetablingCriterion;
    007import org.cpsolver.coursett.model.Lecture;
    008import org.cpsolver.coursett.model.Placement;
    009import org.cpsolver.coursett.model.RoomLocation;
    010import org.cpsolver.ifs.assignment.Assignment;
    011import org.cpsolver.ifs.util.DataProperties;
    012
    013
    014/**
    015 * Cost for using room(s) that are too big. I.e., a difference between size of the assigned room and the size of the
    016 * smallest room in which the class can be placed {@link Lecture#minRoomSize()}.
    017 * <br><br>
    018 * A weight for room size penalty can be set by problem property Comparator.RoomSizeWeight.
    019 * <br><br>
    020 * The difference function can be made polynomial by using Comparator.RoomSizeFactor parameter
    021 * (defaults to 1.05). The value of this criteria is then cubed by the power of this room
    022 * size factor. This is to be able to favor a room swap between two classes at the same time,
    023 * in which a smaller class takes a smaller room. To do this, set Comparator.RoomSizeFactor to
    024 * a number bigger than one that is close to one (e.g., 1.05).
    025 *
    026 * <br>
    027 *
    028 * @author  Tomáš Müller
    029 * @version CourseTT 1.3 (University Course Timetabling)<br>
    030 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    031 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    032 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    033 * <br>
    034 *          This library is free software; you can redistribute it and/or modify
    035 *          it under the terms of the GNU Lesser General Public License as
    036 *          published by the Free Software Foundation; either version 3 of the
    037 *          License, or (at your option) any later version. <br>
    038 * <br>
    039 *          This library is distributed in the hope that it will be useful, but
    040 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    041 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    042 *          Lesser General Public License for more details. <br>
    043 * <br>
    044 *          You should have received a copy of the GNU Lesser General Public
    045 *          License along with this library; if not see
    046 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    047 */
    048public class RoomSizePenalty extends TimetablingCriterion {
    049    private double iRoomSizeFactor = 1.0;
    050
    051    @Override
    052    public void configure(DataProperties properties) {
    053        super.configure(properties);
    054        iRoomSizeFactor = properties.getPropertyDouble("Comparator.RoomSizeFactor", 1.05);
    055    }
    056
    057    @Override
    058    public double getWeightDefault(DataProperties config) {
    059        return config.getPropertyDouble("Comparator.RoomSizeWeight", 0.001);
    060    }
    061
    062    @Override
    063    public String getPlacementSelectionWeightName() {
    064        return "Placement.RoomSizeWeight";
    065    }
    066
    067    @Override
    068    public double getValue(Assignment<Lecture, Placement> assignment, Placement value, Set<Placement> conflicts) {
    069        if (value.variable().getNrRooms() <= 0) return 0.0;
    070        double size = 0;
    071        if (value.getRoomLocation() != null)
    072            size = value.getRoomLocation().getRoomSize();
    073        else if (value.getRoomLocations() != null) {
    074            for (RoomLocation room: value.getRoomLocations())
    075                size += room.getRoomSize();
    076            size /= value.getNrRooms();
    077        }
    078        double diff = size - value.variable().minRoomSize();
    079        return (diff < 0 ? 0 : Math.pow(diff, iRoomSizeFactor));
    080    }
    081
    082    @Override
    083    public void getInfo(Assignment<Lecture, Placement> assignment, Map<String, String> info) {
    084        if (getValue(assignment) != 0.0)
    085            info.put(getName(), sDoubleFormat.format(Math.pow(getValue(assignment) / getModel().nrAssignedVariables(assignment), 1.0 / iRoomSizeFactor)));
    086    }
    087
    088}