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.ExamModel; 009import org.cpsolver.exam.model.ExamPlacement; 010import org.cpsolver.ifs.assignment.Assignment; 011import org.cpsolver.ifs.util.DataProperties; 012 013 014/** 015 * Front load penalty. I.e., large exam is discouraged to be placed on or after a 016 * certain period. 017 * <br><br> 018 * <b>largeSize</b>: An exam is considered large, if its size is greater or equal to 019 * this number. Value -1 means all exams are small. It can be set by problem 020 * property Exams.LargeSize, or in the input xml file, property largeSize. 021 * <br><br> 022 * <b>largePeriod</b>: Period index (number of periods multiplied by this number) for front load 023 * criteria for large exams. Can be set by problem property 024 * Exams.LargePeriod, or in the input xml file, property largePeriod. 025 * <br><br> 026 * Weight of the front load criterion, i.e., a weight for assigning a large exam 027 * after large period can be set by problem property Exams.LargeWeight, or 028 * in the input xml file, property largeWeight. 029 * 030 * <br> 031 * 032 * @version ExamTT 1.3 (Examination Timetabling)<br> 033 * Copyright (C) 2008 - 2014 Tomáš Müller<br> 034 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 035 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 036 * <br> 037 * This library is free software; you can redistribute it and/or modify 038 * it under the terms of the GNU Lesser General Public License as 039 * published by the Free Software Foundation; either version 3 of the 040 * License, or (at your option) any later version. <br> 041 * <br> 042 * This library is distributed in the hope that it will be useful, but 043 * WITHOUT ANY WARRANTY; without even the implied warranty of 044 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 045 * Lesser General Public License for more details. <br> 046 * <br> 047 * You should have received a copy of the GNU Lesser General Public 048 * License along with this library; if not see 049 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 050 */ 051public class LargeExamsPenalty extends ExamCriterion { 052 private int iLargeSize = -1; 053 private double iLargePeriod = 0.67; 054 055 @Override 056 public String getWeightName() { 057 return "Exams.LargeWeight"; 058 } 059 060 @Override 061 public String getXmlWeightName() { 062 return "largeWeight"; 063 } 064 065 @Override 066 public void getXmlParameters(Map<String, String> params) { 067 params.put(getXmlWeightName(), String.valueOf(getWeight())); 068 params.put("largeSize", String.valueOf(getLargeSize())); 069 params.put("largePeriod", String.valueOf(getLargePeriod())); 070 } 071 072 @Override 073 public void setXmlParameters(Map<String, String> params) { 074 try { 075 setWeight(Double.valueOf(params.get(getXmlWeightName()))); 076 } catch (NumberFormatException e) {} catch (NullPointerException e) {} 077 try { 078 setLargeSize(Integer.valueOf(params.get("largeSize"))); 079 } catch (NumberFormatException e) {} catch (NullPointerException e) {} 080 try { 081 setLargePeriod(Double.valueOf(params.get("largePeriod"))); 082 } catch (NumberFormatException e) {} catch (NullPointerException e) {} 083 } 084 085 @Override 086 public double getWeightDefault(DataProperties config) { 087 return 1.0; 088 } 089 090 @Override 091 public void configure(DataProperties properties) { 092 super.configure(properties); 093 iLargeSize = properties.getPropertyInt("Exams.LargeSize", iLargeSize); 094 iLargePeriod = properties.getPropertyDouble("Exams.LargePeriod", iLargePeriod); 095 } 096 097 /** 098 * An exam is considered large, if its size is greater or equal to this 099 * large size. Value -1 means all exams are small. Can be set by problem 100 * property Exams.LargeSize, or in the input xml file, property largeSize) 101 * @return large size 102 **/ 103 public int getLargeSize() { 104 return iLargeSize; 105 } 106 107 /** 108 * An exam is considered large, if its size is greater or equal to this 109 * large size. Value -1 means all exams are small. Can be set by problem 110 * property Exams.LargeSize, or in the input xml file, property largeSize) 111 * @param largeSize large size 112 **/ 113 public void setLargeSize(int largeSize) { 114 iLargeSize = largeSize; 115 } 116 117 /** 118 * Period index (number of periods multiplied by this number) for front load 119 * criteria for large exams. Can be set by problem property 120 * Exams.LargePeriod, or in the input xml file, property largePeriod) 121 * @return large period 122 **/ 123 public double getLargePeriod() { 124 return iLargePeriod; 125 } 126 127 /** 128 * Period index (number of periods multiplied by this number) for front load 129 * criteria for large exams. Can be set by problem property 130 * Exams.LargePeriod, or in the input xml file, property largePeriod) 131 * @param largePeriod large period 132 **/ 133 public void setLargePeriod(double largePeriod) { 134 iLargePeriod = largePeriod; 135 } 136 137 138 public int getLargePeriodIndex() { 139 return (int) Math.round(((ExamModel)getModel()).getPeriods().size() * iLargePeriod); 140 } 141 142 @Override 143 public double getValue(Assignment<Exam, ExamPlacement> assignment, ExamPlacement value, Set<ExamPlacement> conflicts) { 144 Exam exam = value.variable(); 145 if (getLargeSize() < 0 || exam.getSize() < getLargeSize()) return 0; 146 return (value.getPeriod().getIndex() < getLargePeriodIndex() ? 0 : 1); 147 } 148 149 @Override 150 public double[] getBounds(Assignment<Exam, ExamPlacement> assignment, Collection<Exam> variables) { 151 double[] bounds = new double[] { 0.0, 0.0 }; 152 for (Exam exam : variables) { 153 if (getLargeSize() >= 0 && exam.getSize() >= getLargeSize()) 154 bounds[1] += 1.0; 155 } 156 return bounds; 157 } 158 159 @Override 160 public String toString(Assignment<Exam, ExamPlacement> assignment) { 161 return (getValue(assignment) <= 0.0 ? "" : "LP:" + sDoubleFormat.format(getValue(assignment))); 162 } 163}