001    package net.sf.cpsolver.exam.criteria;
002    
003    import java.util.Set;
004    
005    import net.sf.cpsolver.exam.model.ExamDistributionConstraint;
006    import net.sf.cpsolver.exam.model.ExamModel;
007    import net.sf.cpsolver.exam.model.ExamPlacement;
008    import net.sf.cpsolver.ifs.util.DataProperties;
009    
010    /**
011     * Distribution penalty. I.e., sum weights of violated distribution
012     * constraints.
013     * <br><br>
014     * A weight of violated distribution soft constraints (see
015     * {@link ExamDistributionConstraint}) can be set by problem property
016     * Exams.RoomDistributionWeight, or in the input xml file, property
017     * roomDistributionWeight.
018     * 
019     * <br>
020     * 
021     * @version ExamTT 1.2 (Examination Timetabling)<br>
022     *          Copyright (C) 2008 - 2012 Tomas Muller<br>
023     *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
024     *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
025     * <br>
026     *          This library is free software; you can redistribute it and/or modify
027     *          it under the terms of the GNU Lesser General Public License as
028     *          published by the Free Software Foundation; either version 3 of the
029     *          License, or (at your option) any later version. <br>
030     * <br>
031     *          This library is distributed in the hope that it will be useful, but
032     *          WITHOUT ANY WARRANTY; without even the implied warranty of
033     *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
034     *          Lesser General Public License for more details. <br>
035     * <br>
036     *          You should have received a copy of the GNU Lesser General Public
037     *          License along with this library; if not see
038     *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
039     */
040    public class DistributionPenalty extends ExamCriterion {
041        
042        public DistributionPenalty() {
043            iValueUpdateType = ValueUpdateType.NoUpdate; 
044        }
045        
046        @Override
047        public String getWeightName() {
048            return "Exams.DistributionWeight";
049        }
050        
051        @Override
052        public String getXmlWeightName() {
053            return "distributionWeight";
054        }
055        
056        @Override
057        public double getWeightDefault(DataProperties config) {
058            return 1.0;
059        }
060    
061        @Override
062        public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) {
063            int penalty = 0;
064            for (ExamDistributionConstraint dc : value.variable().getDistributionConstraints()) {
065                if (dc.isHard())
066                    continue;
067                boolean sat = dc.isSatisfied(value);
068                if (sat != dc.isSatisfied())
069                    penalty += (sat ? -dc.getWeight() : dc.getWeight());
070            }
071            return penalty;
072        }
073        
074        @Override
075        public boolean isRoomCriterion() { return true; }
076        
077        /**
078         * Room related distribution penalty, i.e., sum weights of violated
079         * distribution constraints
080         */
081        @Override
082        public double getRoomValue(ExamPlacement value) {
083            int penalty = 0;
084            for (ExamDistributionConstraint dc : value.variable().getDistributionConstraints()) {
085                if (dc.isHard() || !dc.isRoomRelated())
086                    continue;
087                boolean sat = dc.isSatisfied(value);
088                if (sat != dc.isSatisfied())
089                    penalty += (sat ? -dc.getWeight() : dc.getWeight());
090            }
091            return penalty;
092        }
093    
094        
095        @Override
096        public boolean isPeriodCriterion() { return true; }
097        
098        /**
099         * Period related distribution penalty, i.e., sum weights of violated
100         * distribution constraints
101         */
102        @Override
103        public double getPeriodValue(ExamPlacement value) {
104            int penalty = 0;
105            for (ExamDistributionConstraint dc : value.variable().getDistributionConstraints()) {
106                if (dc.isHard() || !dc.isPeriodRelated())
107                    continue;
108                boolean sat = dc.isSatisfied(value);
109                if (sat != dc.isSatisfied())
110                    penalty += (sat ? -dc.getWeight() : dc.getWeight());
111            }
112            return penalty;
113        }
114        
115        @Override
116        protected void computeBounds() {
117            iBounds = new double[] { 0.0, 0.0 };
118            for (ExamDistributionConstraint dc : ((ExamModel)getModel()).getDistributionConstraints()) {
119                if (dc.isHard())
120                    continue;
121                iBounds[1] += dc.getWeight();
122            }
123        }
124    
125        @Override
126        public String toString() {
127            return "DP:" + sDoubleFormat.format(getWeightedValue());
128        }
129    }