001package org.cpsolver.coursett.criteria.additional; 002 003import java.util.Map; 004import java.util.Set; 005 006import org.cpsolver.coursett.criteria.TimetablingCriterion; 007import org.cpsolver.coursett.model.Lecture; 008import org.cpsolver.coursett.model.Placement; 009import org.cpsolver.coursett.model.RoomLocation; 010import org.cpsolver.ifs.assignment.Assignment; 011import org.cpsolver.ifs.solver.Solver; 012import org.cpsolver.ifs.util.DataProperties; 013 014 015/** 016 * Cost for using room(s) that are too big. I.e., a difference between size of the assigned room and the size of the 017 * smallest room in which the class can be placed {@link Lecture#minRoomSize()}. 018 * <br><br> 019 * A weight for room size penalty can be set by problem property Comparator.RoomSizeWeight. 020 * <br><br> 021 * The difference function can be made polynomial by using Comparator.RoomSizeFactor parameter 022 * (defaults to 1.05). The value of this criteria is then cubed by the power of this room 023 * size factor. This is to be able to favor a room swap between two classes at the same time, 024 * in which a smaller class takes a smaller room. To do this, set Comparator.RoomSizeFactor to 025 * a number bigger than one that is close to one (e.g., 1.05). 026 * 027 * <br> 028 * 029 * @version CourseTT 1.3 (University Course Timetabling)<br> 030 * Copyright (C) 2006 - 2014 Tomas Muller<br> 031 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 032 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 033 * <br> 034 * This library is free software; you can redistribute it and/or modify 035 * it under the terms of the GNU Lesser General Public License as 036 * published by the Free Software Foundation; either version 3 of the 037 * License, or (at your option) any later version. <br> 038 * <br> 039 * This library is distributed in the hope that it will be useful, but 040 * WITHOUT ANY WARRANTY; without even the implied warranty of 041 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 042 * Lesser General Public License for more details. <br> 043 * <br> 044 * You should have received a copy of the GNU Lesser General Public 045 * License along with this library; if not see 046 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 047 */ 048public class RoomSizePenalty extends TimetablingCriterion { 049 private double iRoomSizeFactor = 1.0; 050 051 @Override 052 public boolean init(Solver<Lecture, Placement> solver) { 053 super.init(solver); 054 iRoomSizeFactor = solver.getProperties().getPropertyDouble("Comparator.RoomSizeFactor", 1.05); 055 return true; 056 } 057 058 @Override 059 public double getWeightDefault(DataProperties config) { 060 return config.getPropertyDouble("Comparator.RoomSizeWeight", 0.001); 061 } 062 063 @Override 064 public String getPlacementSelectionWeightName() { 065 return "Placement.RoomSizeWeight"; 066 } 067 068 @Override 069 public double getValue(Assignment<Lecture, Placement> assignment, Placement value, Set<Placement> conflicts) { 070 if (value.variable().getNrRooms() <= 0) return 0.0; 071 double size = 0; 072 if (value.getRoomLocation() != null) 073 size = value.getRoomLocation().getRoomSize(); 074 else if (value.getRoomLocations() != null) { 075 for (RoomLocation room: value.getRoomLocations()) 076 size += room.getRoomSize(); 077 size /= value.getNrRooms(); 078 } 079 double diff = size - value.variable().minRoomSize(); 080 return (diff < 0 ? 0 : Math.pow(diff, iRoomSizeFactor)); 081 } 082 083 @Override 084 public void getInfo(Assignment<Lecture, Placement> assignment, Map<String, String> info) { 085 if (getValue(assignment) != 0.0) 086 info.put(getName(), sDoubleFormat.format(Math.pow(getValue(assignment) / getModel().nrAssignedVariables(assignment), 1.0 / iRoomSizeFactor))); 087 } 088 089}