001 package net.sf.cpsolver.coursett.criteria;
002
003 import net.sf.cpsolver.coursett.constraint.JenrlConstraint;
004 import net.sf.cpsolver.coursett.model.Lecture;
005 import net.sf.cpsolver.coursett.model.Placement;
006 import net.sf.cpsolver.coursett.model.TimeLocation;
007 import net.sf.cpsolver.ifs.util.DataProperties;
008 import net.sf.cpsolver.ifs.util.DistanceMetric;
009
010 /**
011 * Student distance conflicts. This criterion counts student distance conflicts between classes.
012 * A distance conflict occurs when two classes that are attended by the same student (or students)
013 * are placed back-to-back in rooms that are too far a part. The combinations of classes
014 * that share students are maintained by {@link JenrlConstraint}. The critical distance is measured
015 * by {@link DistanceMetric#getDistanceInMinutes(double, double, double, double)} and compared
016 * witch class break time {@link TimeLocation#getBreakTime()}.
017 * <br>
018 *
019 * @version CourseTT 1.2 (University Course Timetabling)<br>
020 * Copyright (C) 2006 - 2011 Tomas Muller<br>
021 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
022 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
023 * <br>
024 * This library is free software; you can redistribute it and/or modify
025 * it under the terms of the GNU Lesser General Public License as
026 * published by the Free Software Foundation; either version 3 of the
027 * License, or (at your option) any later version. <br>
028 * <br>
029 * This library is distributed in the hope that it will be useful, but
030 * WITHOUT ANY WARRANTY; without even the implied warranty of
031 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
032 * Lesser General Public License for more details. <br>
033 * <br>
034 * You should have received a copy of the GNU Lesser General Public
035 * License along with this library; if not see
036 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
037 */
038 public class StudentDistanceConflict extends StudentConflict {
039
040 @Override
041 public boolean inConflict(Placement p1, Placement p2) {
042 return !ignore(p1, p2) && distance(getMetrics(), p1, p2);
043 }
044
045 @Override
046 public boolean isApplicable(Lecture l1, Lecture l2) {
047 return !ignore(l1, l2) && applicable(l1, l2); // all student conflicts (including committed)
048 }
049
050 @Override
051 public double getWeightDefault(DataProperties config) {
052 return config.getPropertyDouble("Comparator.DistStudentConflictWeight", 0.2);
053 }
054
055 @Override
056 public String getPlacementSelectionWeightName() {
057 return "Placement.NrDistStudConfsWeight";
058 }
059
060
061 }