001package org.cpsolver.coursett.criteria;
002
003import java.util.Collection;
004import java.util.Set;
005
006import org.cpsolver.coursett.Constants;
007import org.cpsolver.coursett.model.Lecture;
008import org.cpsolver.coursett.model.Placement;
009import org.cpsolver.coursett.model.RoomLocation;
010import org.cpsolver.coursett.preference.PreferenceCombination;
011import org.cpsolver.ifs.assignment.Assignment;
012import org.cpsolver.ifs.util.DataProperties;
013
014
015/**
016 * Too big rooms. This criterion counts cases where a class is placed in a room
017 * that is too big for the class. In general, a room is discouraged (in this
018 * criterion) if it has 25% more space than needed, strongly discouraged
019 * if it has more than 50% space than needed. Needed space is counted as the space
020 * of the smallest room in which a class can take place.
021 * <br>
022 * 
023 * @version CourseTT 1.3 (University Course Timetabling)<br>
024 *          Copyright (C) 2006 - 2014 Tomas Muller<br>
025 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
026 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
027 * <br>
028 *          This library is free software; you can redistribute it and/or modify
029 *          it under the terms of the GNU Lesser General Public License as
030 *          published by the Free Software Foundation; either version 3 of the
031 *          License, or (at your option) any later version. <br>
032 * <br>
033 *          This library is distributed in the hope that it will be useful, but
034 *          WITHOUT ANY WARRANTY; without even the implied warranty of
035 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
036 *          Lesser General Public License for more details. <br>
037 * <br>
038 *          You should have received a copy of the GNU Lesser General Public
039 *          License along with this library; if not see
040 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
041 */
042public class TooBigRooms extends TimetablingCriterion {
043    
044    @Override
045    public double getWeightDefault(DataProperties config) {
046        return config.getPropertyDouble("Comparator.TooBigRoomWeight", 0.1);
047    }
048    
049    @Override
050    public String getPlacementSelectionWeightName() {
051        return "Placement.TooBigRoomWeight";
052    }
053
054    @Override
055    public double getValue(Assignment<Lecture, Placement> assignment, Placement value, Set<Placement> conflicts) {
056        double ret = getTooBigRoomPreference(value);
057        if (conflicts != null)
058            for (Placement conflict: conflicts)
059                ret -= getTooBigRoomPreference(conflict);
060        return ret;
061    }
062    
063    @Override
064    public double[] getBounds(Assignment<Lecture, Placement> assignment, Collection<Lecture> variables) {
065        double[] bounds = new double[] { 0.0, 0.0 };
066        for (Lecture lect: variables) {
067            if (lect.getNrRooms() > 0)
068                bounds[0] += Constants.sPreferenceLevelStronglyDiscouraged;
069        }
070        return bounds;
071    }
072    
073    public static long getDiscouragedRoomSize(Placement value) {
074        return Math.round(1.25 * value.variable().minRoomSize());
075    }
076
077    public static long getStronglyDiscouragedRoomSize(Placement value) {
078        return Math.round(1.5 * value.variable().minRoomSize());
079    }
080    
081    public static int getTooBigRoomPreference(Placement value) {
082        if (value.isMultiRoom()) {
083            PreferenceCombination pref = PreferenceCombination.getDefault();
084            for (RoomLocation r : value.getRoomLocations()) {
085                if (r.getRoomSize() > getStronglyDiscouragedRoomSize(value))
086                    pref.addPreferenceInt(Constants.sPreferenceLevelStronglyDiscouraged);
087                else if (r.getRoomSize() > getDiscouragedRoomSize(value))
088                    pref.addPreferenceInt(Constants.sPreferenceLevelDiscouraged);
089            }
090            return pref.getPreferenceInt();
091        } else {
092            if (value.getRoomLocation().getRoomSize() > getStronglyDiscouragedRoomSize(value))
093                return Constants.sPreferenceLevelStronglyDiscouraged;
094            else if (value.getRoomLocation().getRoomSize() > getDiscouragedRoomSize(value))
095                return Constants.sPreferenceLevelDiscouraged;
096            else
097                return Constants.sPreferenceLevelNeutral;
098        }
099    }
100    
101}