001package org.cpsolver.coursett.criteria.additional; 002 003import org.cpsolver.coursett.constraint.JenrlConstraint; 004import org.cpsolver.coursett.criteria.StudentConflict; 005import org.cpsolver.coursett.model.Lecture; 006import org.cpsolver.coursett.model.Placement; 007import org.cpsolver.coursett.model.Student; 008import org.cpsolver.ifs.assignment.Assignment; 009import org.cpsolver.ifs.util.DataProperties; 010 011/** 012 * Quadratic student conflicts. Same as {@link StudentConflict}, however, 013 * student joint enrollments are squared (1 conflict counts as 1, 2 as 4, 3 as 9, etc.). 014 * 015 * <br> 016 * 017 * @version CourseTT 1.3 (University Course Timetabling)<br> 018 * Copyright (C) 2006 - 2014 Tomáš Müller<br> 019 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 020 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 021 * <br> 022 * This library is free software; you can redistribute it and/or modify 023 * it under the terms of the GNU Lesser General Public License as 024 * published by the Free Software Foundation; either version 3 of the 025 * License, or (at your option) any later version. <br> 026 * <br> 027 * This library is distributed in the hope that it will be useful, but 028 * WITHOUT ANY WARRANTY; without even the implied warranty of 029 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 030 * Lesser General Public License for more details. <br> 031 * <br> 032 * You should have received a copy of the GNU Lesser General Public 033 * License along with this library; if not see 034 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 035 */ 036 037public class QuadraticStudentConflict extends StudentConflict { 038 039 @Override 040 public boolean isApplicable(Lecture l1, Lecture l2) { 041 return l1 != null && l2 != null && !ignore(l1, l2) && applicable(l1, l2); 042 } 043 044 @Override 045 public double getWeightDefault(DataProperties config) { 046 return config.getPropertyDouble("Comparator.StudentConflictWeight", 1.0); 047 } 048 049 @Override 050 public String getPlacementSelectionWeightName() { 051 return "Placement.NrStudConfsWeight"; 052 } 053 054 @Override 055 protected double jointEnrollment(JenrlConstraint jenrl) { 056 return jenrl.jenrl() * jenrl.jenrl(); 057 } 058 059 @Override 060 public void incJenrl(Assignment<Lecture, Placement> assignment, JenrlConstraint jenrl, double studentWeight, Double conflictPriority, Student student) { 061 if (isApplicable(jenrl.first(), jenrl.second()) && inConflict(assignment.getValue(jenrl.first()), assignment.getValue(jenrl.second()))) { 062 inc(assignment, (jenrl.jenrl() * jenrl.jenrl()) - (jenrl.jenrl() - studentWeight) * (jenrl.jenrl() - studentWeight)); 063 } 064 } 065 066}