001package net.sf.cpsolver.exam.criteria.additional; 002 003import java.util.Map; 004import java.util.Set; 005 006import net.sf.cpsolver.exam.criteria.ExamCriterion; 007import net.sf.cpsolver.exam.model.ExamPlacement; 008import net.sf.cpsolver.exam.model.ExamRoomPlacement; 009import net.sf.cpsolver.ifs.util.DataProperties; 010 011/** 012 * Experimental criterion measuring average distance (in meters) to the 013 * strongly preferred room (or rooms) of the examination. The idea is to 014 * prefer rooms that are close to the strongly preference room (if there is 015 * a strongly preferred room but it is not available). 016 * <br><br> 017 * A weight of the average distance between the assigned room(s) and the 018 * strongly preferred room or rooms can be set using 019 * Exams.DistanceToStronglyPreferredRoomWeight property. 020 * <br><br> 021 * To enable this criterion add this class name to Exams.AdditionalCriteria 022 * parameter. For instance:<br> 023 * Exams.AdditionalCriteria=net.sf.cpsolver.exam.criteria.additional.DistanceToStronglyPreferredRoom 024 * 025 * <br> 026 * 027 * @version ExamTT 1.2 (Examination Timetabling)<br> 028 * Copyright (C) 2008 - 2012 Tomáš Müller<br> 029 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 030 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 031 * <br> 032 * This library is free software; you can redistribute it and/or modify 033 * it under the terms of the GNU Lesser General Public License as 034 * published by the Free Software Foundation; either version 3 of the 035 * License, or (at your option) any later version. <br> 036 * <br> 037 * This library is distributed in the hope that it will be useful, but 038 * WITHOUT ANY WARRANTY; without even the implied warranty of 039 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 040 * Lesser General Public License for more details. <br> 041 * <br> 042 * You should have received a copy of the GNU Lesser General Public 043 * License along with this library; if not see 044 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 045 */ 046public class DistanceToStronglyPreferredRoom extends ExamCriterion { 047 048 @Override 049 public String getWeightName() { 050 return "Exams.DistanceToStronglyPreferredRoomWeight"; 051 } 052 053 @Override 054 public String getXmlWeightName() { 055 return "distanceToStronglyPreferredRoomWeight"; 056 } 057 058 @Override 059 public double getWeightDefault(DataProperties config) { 060 return 0.001; 061 } 062 063 @Override 064 public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) { 065 Average ret = new Average(); 066 for (ExamRoomPlacement assigned: value.getRoomPlacements()) { 067 for (ExamRoomPlacement preferred: value.variable().getRoomPlacements()) { 068 if (preferred.getPenalty() < -2) // strongly preferred 069 ret.add(assigned.getDistanceInMeters(preferred)); 070 } 071 } 072 return ret.average(); 073 } 074 075 @Override 076 public String toString() { 077 return "@D:" + sDoubleFormat.format(getValue() / getModel().assignedVariables().size()); 078 } 079 080 @Override 081 public double[] getBounds() { 082 return new double[] { 0.0, 0.0 }; 083 } 084 085 @Override 086 public void getInfo(Map<String, String> info) { 087 if (getValue() > 0.0) 088 info.put(getName(), sDoubleFormat.format(getValue() / getModel().assignedVariables().size()) + " m"); 089 } 090 091 private static class Average { 092 double iValue = 0.0; 093 int iCount = 0; 094 095 private void add(double value) { 096 iValue += value; iCount ++; 097 } 098 099 public double average() { 100 return (iCount == 0 ? 0.0 : iValue / iCount); 101 } 102 } 103 104}