001package net.sf.cpsolver.ifs.criteria; 002 003import java.util.Collection; 004import java.util.Set; 005 006import net.sf.cpsolver.ifs.model.InfoProvider; 007import net.sf.cpsolver.ifs.model.ModelListener; 008import net.sf.cpsolver.ifs.model.Value; 009import net.sf.cpsolver.ifs.model.Variable; 010 011/** 012 * Criterion. <br> 013 * <br> 014 * An optimization objective can be split into several (optimization) criteria 015 * and modeled as a weighted sum of these. This makes the implementation of a particular problem 016 * more versatile as it allows for an easier modification of the optimization objective. 017 * 018 * @version IFS 1.2 (Iterative Forward Search)<br> 019 * Copyright (C) 2006 - 2011 Tomáš Müller<br> 020 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 021 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 022 * <br> 023 * This library is free software; you can redistribute it and/or modify 024 * it under the terms of the GNU Lesser General Public License as 025 * published by the Free Software Foundation; either version 3 of the 026 * License, or (at your option) any later version. <br> 027 * <br> 028 * This library is distributed in the hope that it will be useful, but 029 * WITHOUT ANY WARRANTY; without even the implied warranty of 030 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 031 * Lesser General Public License for more details. <br> 032 * <br> 033 * You should have received a copy of the GNU Lesser General Public 034 * License along with this library; if not see 035 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 036 */ 037public interface Criterion<V extends Variable<V, T>, T extends Value<V, T>> extends ModelListener<V, T>, InfoProvider<V> { 038 039 /** Current value of the criterion (optimization objective) */ 040 public double getValue(); 041 042 /** Weighted value of the objectives */ 043 public double getWeightedValue(); 044 045 /** Bounds (minimum and maximum) estimate for the value */ 046 public double[] getBounds(); 047 048 /** Weighted best value of the objective (value in the best solution). */ 049 public double getWeightedBest(); 050 051 /** Best value (value of the criterion in the best solution) */ 052 public double getBest(); 053 054 /** Weight of the criterion */ 055 public double getWeight(); 056 057 /** Weighted value of a proposed assignment (including hard conflicts) */ 058 public double getWeightedValue(T value, Set<T> conflicts); 059 060 /** Value of a proposed assignment (including hard conflicts) */ 061 public double getValue(T value, Set<T> conflicts); 062 063 /** Weighted value of a part of the problem (given by the collection of variables) */ 064 public double getWeightedValue(Collection<V> variables); 065 066 /** Value of a part of the problem (given by the collection of variables) */ 067 public double getValue(Collection<V> variables); 068 069 /** Value bounds (minimum and maximum) of the criterion on a part of the problem */ 070 public double[] getBounds(Collection<V> variables); 071 072 /** Criterion name */ 073 public String getName(); 074 075 /** Outside update of the criterion (usefull when the criterion is driven by a set of constraints). */ 076 public void inc(double value); 077 078 /** Notification that the current solution has been saved to the best. */ 079 public void bestSaved(); 080 081 /** Notification that the current solution has been restored from the best. */ 082 public void bestRestored(); 083}