    001package net.sf.cpsolver.exam.criteria;
    002
    003import java.util.Set;
    004
    005import net.sf.cpsolver.exam.model.Exam;
    006import net.sf.cpsolver.exam.model.ExamInstructor;
    007import net.sf.cpsolver.exam.model.ExamModel;
    008import net.sf.cpsolver.exam.model.ExamPeriod;
    009import net.sf.cpsolver.exam.model.ExamPlacement;
    010import net.sf.cpsolver.ifs.util.DataProperties;
    011
    012/**
    013 * Number of back-to-back distance instructor conflicts. I.e., number of
    014 * cases when an exam is attended by an instructor that attends some other
    015 * exam at the previous {@link ExamPeriod#prev()} or following
    016 * {@link ExamPeriod#next()} period and the distance
    017 * {@link ExamPlacement#getDistanceInMeters(ExamPlacement)} between these two exams
    018 * is greater than {@link ExamModel#getBackToBackDistance()}. Distance
    019 * back-to-back conflicts are only considered between consecutive periods
    020 * that are of the same day.
    021 * <br><br>
    022 * Distance back-to-back instructor conflict weight can be set by problem
    023 * property Exams.InstructorDistanceBackToBackConflictWeight, or in the
    024 * input xml file, property instructorDistanceBackToBackConflictWeight.
    025 *
    026 * <br>
    027 *
    028 * @version ExamTT 1.2 (Examination Timetabling)<br>
    029 *          Copyright (C) 2008 - 2012 Tomáš Müller<br>
    030 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    031 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    032 * <br>
    033 *          This library is free software; you can redistribute it and/or modify
    034 *          it under the terms of the GNU Lesser General Public License as
    035 *          published by the Free Software Foundation; either version 3 of the
    036 *          License, or (at your option) any later version. <br>
    037 * <br>
    038 *          This library is distributed in the hope that it will be useful, but
    039 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    040 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    041 *          Lesser General Public License for more details. <br>
    042 * <br>
    043 *          You should have received a copy of the GNU Lesser General Public
    044 *          License along with this library; if not see
    045 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    046 */
    047public class InstructorDistanceBackToBackConflicts extends StudentDistanceBackToBackConflicts {
    048
    049    @Override
    050    public String getWeightName() {
    051        return "Exams.InstructorDistanceBackToBackConflictWeight";
    052    }
    053
    054    @Override
    055    public String getXmlWeightName() {
    056        return "instructorDistanceBackToBackConflictWeight";
    057    }
    058
    059    @Override
    060    public double getWeightDefault(DataProperties config) {
    061        return 25.0;
    062    }
    063
    064    @Override
    065    public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) {
    066        Exam exam = value.variable();
    067        double btbDist = getBackToBackDistance();
    068        if (btbDist < 0)
    069            return 0;
    070        int penalty = 0;
    071        for (ExamInstructor s : exam.getInstructors()) {
    072            if (value.getPeriod().prev() != null) {
    073                if (value.getPeriod().prev().getDay() == value.getPeriod().getDay()) {
    074                    for (Exam x : s.getExams(value.getPeriod().prev())) {
    075                        if (x.equals(exam))
    076                            continue;
    077                        if (value.getDistanceInMeters(x.getAssignment()) > btbDist)
    078                            penalty++;
    079                    }
    080                }
    081            }
    082            if (value.getPeriod().next() != null) {
    083                if (value.getPeriod().next().getDay() == value.getPeriod().getDay()) {
    084                    for (Exam x : s.getExams(value.getPeriod().next())) {
    085                        if (x.equals(exam))
    086                            continue;
    087                        if (value.getDistanceInMeters(x.getAssignment()) > btbDist)
    088                            penalty++;
    089                    }
    090                }
    091            }
    092        }
    093        return penalty;
    094    }
    095
    096    @Override
    097    public String getName() {
    098        return "Instructor Distance Back-To-Back Conflicts";
    099    }
    100
    101    @Override
    102    public String toString() {
    103        return (getValue() <= 0.0 ? "" : "iBTBd:" + sDoubleFormat.format(getValue()));
    104    }
    105
    106    @Override
    107    public boolean isPeriodCriterion() { return false; }
    108}