    001package org.cpsolver.exam.criteria;
    002
    003import java.util.Collection;
    004import java.util.Map;
    005import java.util.Set;
    006
    007import org.cpsolver.exam.model.Exam;
    008import org.cpsolver.exam.model.ExamPeriodPlacement;
    009import org.cpsolver.exam.model.ExamPlacement;
    010import org.cpsolver.ifs.assignment.Assignment;
    011import org.cpsolver.ifs.util.DataProperties;
    012
    013
    014/**
    015 * A weight for period penalty (used in
    016 * {@link ExamPeriodPlacement#getPenalty()} multiplied by examination size
    017 * {@link Exam#getSize()}. Can be set by problem property
    018 * Exams.PeriodSizeWeight, or in the input xml file, property periodSizeWeight).
    019 *
    020 * <br>
    021 *
    022 * @version ExamTT 1.3 (Examination Timetabling)<br>
    023 *          Copyright (C) 2008 - 2014 Tomáš Müller<br>
    024 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    025 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    026 * <br>
    027 *          This library is free software; you can redistribute it and/or modify
    028 *          it under the terms of the GNU Lesser General Public License as
    029 *          published by the Free Software Foundation; either version 3 of the
    030 *          License, or (at your option) any later version. <br>
    031 * <br>
    032 *          This library is distributed in the hope that it will be useful, but
    033 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    034 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    035 *          Lesser General Public License for more details. <br>
    036 * <br>
    037 *          You should have received a copy of the GNU Lesser General Public
    038 *          License along with this library; if not see
    039 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    040 */
    041public class PeriodSizePenalty extends ExamCriterion {
    042
    043    @Override
    044    public String getWeightName() {
    045        return "Exams.PeriodSizeWeight";
    046    }
    047
    048    @Override
    049    public String getXmlWeightName() {
    050        return "periodSizeWeight";
    051    }
    052
    053    @Override
    054    public double getWeightDefault(DataProperties config) {
    055        return 1.0;
    056    }
    057
    058    @Override
    059    public double getValue(Assignment<Exam, ExamPlacement> assignment, ExamPlacement value, Set<ExamPlacement> conflicts) {
    060        return value.getPeriodPlacement().getPenalty() * (value.variable().getSize() + 1);
    061    }
    062
    063    @Override
    064    public String getName() {
    065        return "Period&times;Size Penalty";
    066    }
    067
    068    @Override
    069    public double[] getBounds(Assignment<Exam, ExamPlacement> assignment, Collection<Exam> variables) {
    070        double[] bounds = new double[] { 0.0, 0.0 };
    071        for (Exam exam : variables) {
    072            if (!exam.getPeriodPlacements().isEmpty()) {
    073                int minSizePenalty = Integer.MAX_VALUE, maxSizePenalty = Integer.MIN_VALUE;
    074                for (ExamPeriodPlacement periodPlacement : exam.getPeriodPlacements()) {
    075                    minSizePenalty = Math.min(minSizePenalty, periodPlacement.getPenalty() * (exam.getSize() + 1));
    076                    maxSizePenalty = Math.max(maxSizePenalty, periodPlacement.getPenalty() * (exam.getSize() + 1));
    077                }
    078                bounds[0] += minSizePenalty;
    079                bounds[1] += maxSizePenalty;
    080            }
    081        }
    082        return bounds;
    083    }
    084
    085    @Override
    086    public void getInfo(Assignment<Exam, ExamPlacement> assignment, Map<String, String> info) {
    087        if (getValue(assignment) != 0.0) {
    088            info.put(getName(), sDoubleFormat.format(getValue(assignment) / assignment.nrAssignedVariables()));
    089        }
    090    }
    091
    092    @Override
    093    public String toString(Assignment<Exam, ExamPlacement> assignment) {
    094        return "PS:" + sDoubleFormat.format(getValue(assignment) / assignment.nrAssignedVariables());
    095    }
    096}