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 * @version ExamTT 1.3 (Examination Timetabling)<br>
030 *          Copyright (C) 2008 - 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 StudentMoreThan1ADayConflicts extends ExamCriterion {
049
050    @Override
051    public String getWeightName() {
052        return "Exams.MoreThanOneADayWeight";
053    }
054    
055    @Override
056    public double getWeightDefault(DataProperties config) {
057        return 1.0;
058    }
059
060    @Override
061    public double getValue(Assignment<Exam, ExamPlacement> assignment, ExamPlacement value, Set<ExamPlacement> conflicts) {
062        Exam exam = value.variable();
063        int penalty = 0;
064        ExamPeriod period = value.getPeriod();
065        Map<ExamStudent, Set<Exam>> students = ((ExamModel)getModel()).getStudentsOfDay(assignment, period);
066        for (ExamStudent s : exam.getStudents()) {
067            Set<Exam> exams = students.get(s);
068            if (exams == null || exams.isEmpty()) continue;
069            int nrExams = exams.size() + (exams.contains(exam) ? 0 : 1);
070            if (nrExams > 1)
071                penalty++;
072        }
073        /*
074        for (ExamStudent s : exam.getStudents()) {
075            Set<Exam> exams = s.getExamsADay(assignment, period);
076            int nrExams = exams.size() + (exams.contains(exam) ? 0 : 1);
077            if (nrExams > 2)
078                penalty++;
079        }
080        */
081        return penalty;
082    }
083    
084    @Override
085    public String getName() {
086        return "More Than 1 A Day Conflicts";
087    }
088    
089    @Override
090    public String getXmlWeightName() {
091        return "moreThanOneADayWeight";
092    }
093
094    @Override
095    public void getInfo(Assignment<Exam, ExamPlacement> assignment, Map<String, String> info) {
096        if (getValue(assignment) != 0.0)
097            info.put(getName(), sDoubleFormat.format(getValue(assignment)));
098    }
099    
100    @Override
101    public double getValue(Assignment<Exam, ExamPlacement> assignment, Collection<Exam> variables) {
102        int ret = 0;
103        ExamModel m = (ExamModel)getModel();
104        Set<Integer> days = new HashSet<Integer>();
105        for (ExamPeriod p: m.getPeriods()) {
106            if (days.add(p.getDay())) {
107                Map<ExamStudent, Set<Exam>> students = ((ExamModel)getModel()).getStudentsOfDay(assignment, p);
108                for (Set<Exam> exams: students.values()) {
109                    int nrExams = exams.size();
110                    if (nrExams > 1)
111                        ret += nrExams - 1;
112                }
113            }
114        }
115        return ret;
116    }
117    
118    @Override
119    public String toString(Assignment<Exam, ExamPlacement> assignment) {
120        return "M1D:" + sDoubleFormat.format(getValue(assignment));
121    }
122}