001package org.cpsolver.exam.criteria.additional;
002
003import java.util.Collection;
004import java.util.HashSet;
005import java.util.Map;
006import java.util.Set;
007
008import org.cpsolver.exam.criteria.ExamCriterion;
009import org.cpsolver.exam.model.Exam;
010import org.cpsolver.exam.model.ExamModel;
011import org.cpsolver.exam.model.ExamPeriod;
012import org.cpsolver.exam.model.ExamPlacement;
013import org.cpsolver.exam.model.ExamStudent;
014import org.cpsolver.ifs.assignment.Assignment;
015import org.cpsolver.ifs.util.DataProperties;
016
017
018/**
019 * Number of more than One exam a day student conflicts. I.e., when an
020 * exam is attended by a student student that attends one or more other
021 * exams at the same day.
022 * <br><br>
023 * More than one exam a day student conflict weight can be set by
024 * problem property Exams.MoreThanOneADayWeight, or in the input
025 * xml file, property moreThanOneADayWeight.
026 * 
027 * <br>
028 * 
029 * @author  Tomáš Müller
030 * @version ExamTT 1.3 (Examination Timetabling)<br>
031 *          Copyright (C) 2008 - 2014 Tomáš Müller<br>
032 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
033 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
034 * <br>
035 *          This library is free software; you can redistribute it and/or modify
036 *          it under the terms of the GNU Lesser General Public License as
037 *          published by the Free Software Foundation; either version 3 of the
038 *          License, or (at your option) any later version. <br>
039 * <br>
040 *          This library is distributed in the hope that it will be useful, but
041 *          WITHOUT ANY WARRANTY; without even the implied warranty of
042 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
043 *          Lesser General Public License for more details. <br>
044 * <br>
045 *          You should have received a copy of the GNU Lesser General Public
046 *          License along with this library; if not see
047 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
048 */
049public class StudentMoreThan1ADayConflicts extends ExamCriterion {
050
051    @Override
052    public String getWeightName() {
053        return "Exams.MoreThanOneADayWeight";
054    }
055    
056    @Override
057    public double getWeightDefault(DataProperties config) {
058        return 1.0;
059    }
060
061    @Override
062    public double getValue(Assignment<Exam, ExamPlacement> assignment, ExamPlacement value, Set<ExamPlacement> conflicts) {
063        Exam exam = value.variable();
064        int penalty = 0;
065        ExamPeriod period = value.getPeriod();
066        Map<ExamStudent, Set<Exam>> students = ((ExamModel)getModel()).getStudentsOfDay(assignment, period);
067        for (ExamStudent s : exam.getStudents()) {
068            Set<Exam> exams = students.get(s);
069            if (exams == null || exams.isEmpty()) continue;
070            int nrExams = exams.size() + (exams.contains(exam) ? 0 : 1);
071            if (nrExams > 1)
072                penalty++;
073        }
074        /*
075        for (ExamStudent s : exam.getStudents()) {
076            Set<Exam> exams = s.getExamsADay(assignment, period);
077            int nrExams = exams.size() + (exams.contains(exam) ? 0 : 1);
078            if (nrExams > 2)
079                penalty++;
080        }
081        */
082        return penalty;
083    }
084    
085    @Override
086    public String getName() {
087        return "More Than 1 A Day Conflicts";
088    }
089    
090    @Override
091    public String getXmlWeightName() {
092        return "moreThanOneADayWeight";
093    }
094
095    @Override
096    public void getInfo(Assignment<Exam, ExamPlacement> assignment, Map<String, String> info) {
097        if (getValue(assignment) != 0.0)
098            info.put(getName(), sDoubleFormat.format(getValue(assignment)));
099    }
100    
101    @Override
102    public double getValue(Assignment<Exam, ExamPlacement> assignment, Collection<Exam> variables) {
103        int ret = 0;
104        ExamModel m = (ExamModel)getModel();
105        Set<Integer> days = new HashSet<Integer>();
106        for (ExamPeriod p: m.getPeriods()) {
107            if (days.add(p.getDay())) {
108                Map<ExamStudent, Set<Exam>> students = ((ExamModel)getModel()).getStudentsOfDay(assignment, p);
109                for (Set<Exam> exams: students.values()) {
110                    int nrExams = exams.size();
111                    if (nrExams > 1)
112                        ret += nrExams - 1;
113                }
114            }
115        }
116        return ret;
117    }
118    
119    @Override
120    public String toString(Assignment<Exam, ExamPlacement> assignment) {
121        return "M1D:" + sDoubleFormat.format(getValue(assignment));
122    }
123}