org.cpsolver.coursett.criteria

Class Perturbations

java.lang.Object

org.cpsolver.ifs.criteria.AbstractCriterion<Lecture,Placement>

org.cpsolver.coursett.criteria.TimetablingCriterion

org.cpsolver.coursett.criteria.Perturbations

All Implemented Interfaces:

CanHoldContext, HasAssignmentContext<Lecture,Placement,AbstractCriterion.ValueContext>, Criterion<Lecture,Placement>, ExtendedInfoProvider<Lecture,Placement>, InfoProvider<Lecture,Placement>, ModelListener<Lecture,Placement>

public class Perturbations
extends TimetablingCriterion

Perturbations. This criterion counts differences (perturbations) between initial and the current solution. It is based on PerturbationsCounter.

Version:

CourseTT 1.3 (University Course Timetabling)
Copyright (C) 2006 - 2014 Tomáš Müller
muller@unitime.org
http://muller.unitime.org

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not see http://www.gnu.org/licenses/.

Author:

Tomáš Müller

Nested Class Summary

Nested classes/interfaces inherited from class org.cpsolver.ifs.criteria.AbstractCriterion

AbstractCriterion.ValueContext, AbstractCriterion.ValueUpdateType

Field Summary

Fields inherited from class org.cpsolver.ifs.criteria.AbstractCriterion

iBest, iDebug, iWeight, sDoubleFormat, sPercentFormat

Fields inherited from interface org.cpsolver.ifs.assignment.context.CanHoldContext

sMaxSize

Constructor Summary

Constructors

Constructor and Description
Perturbations()

Method Summary

Modifier and Type	Method and Description
double[]	getBounds(Assignment<Lecture,Placement> assignment) Bounds (minimum and maximum) estimate for the value
double[]	getBounds(Assignment<Lecture,Placement> assignment, Collection<Lecture> variables) Value bounds (minimum and maximum) of the criterion on a part of the problem
PerturbationsCounter<Lecture,Placement>	getPerturbationsCounter()
String	getPlacementSelectionWeightName()
double	getValue(Assignment<Lecture,Placement> assignment) Current value of the criterion (optimization objective)
double	getValue(Assignment<Lecture,Placement> assignment, Collection<Lecture> variables) Value of a part of the problem (given by the collection of variables)
double	getValue(Assignment<Lecture,Placement> assignment, Placement value, Set<Placement> conflicts) Value of a proposed assignment (including hard conflicts)
double	getWeightDefault(DataProperties config) Defines default weight (when AbstractCriterion.getWeightName() parameter is not present in the criterion).
boolean	init(Solver<Lecture,Placement> solver) Notification that the model was initialized by the solver.

Methods inherited from class org.cpsolver.coursett.criteria.TimetablingCriterion

configure, getPlacementSelectionAdjustmentsName, getPlacementSelectionWeight, getPlacementSelectionWeightDefault

Methods inherited from class org.cpsolver.ifs.criteria.AbstractCriterion

afterAssigned, afterUnassigned, beforeAssigned, beforeUnassigned, bestRestored, bestSaved, clearCache, computeBounds, constraintAdded, constraintRemoved, createAssignmentContext, getAbbreviation, getAssignmentContextReference, getBest, getBounds, getBounds, getContext, getContext, getExtendedInfo, getInfo, getInfo, getModel, getName, getPerc, getPercentage, getPercRev, getValue, getValue, getValueUpdateType, getWeight, getWeightedBest, getWeightedValue, getWeightedValue, getWeightedValue, getWeightedValue, getWeightedValue, getWeightedValue, getWeightName, inc, inc, setAssignmentContextReference, setModel, setValueUpdateType, toString, variableAdded, variableRemoved

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Perturbations

public Perturbations()

Method Detail

getPlacementSelectionWeightName

public String getPlacementSelectionWeightName()

Overrides:

getPlacementSelectionWeightName in class TimetablingCriterion

init

public boolean init(Solver<Lecture,Placement> solver)

Description copied from interface: ModelListener

Notification that the model was initialized by the solver.

Specified by:

init in interface ModelListener<Lecture,Placement>

Overrides:

init in class AbstractCriterion<Lecture,Placement>

Parameters:

solver - IFS solver

Returns:

true if successfully initialized

getWeightDefault

public double getWeightDefault(DataProperties config)

Description copied from class: AbstractCriterion

Defines default weight (when AbstractCriterion.getWeightName() parameter is not present in the criterion).

Overrides:

getWeightDefault in class AbstractCriterion<Lecture,Placement>

Parameters:

config - solver configuration

Returns:

default criterion weight value

getPerturbationsCounter

public PerturbationsCounter<Lecture,Placement> getPerturbationsCounter()

getValue

public double getValue(Assignment<Lecture,Placement> assignment,
                       Placement value,
                       Set<Placement> conflicts)

Description copied from interface: Criterion

Value of a proposed assignment (including hard conflicts)

Parameters:

assignment - current assignment

value - given value

conflicts - values conflicting with the given value

Returns:

change in this criterion value when assigned

getValue

public double getValue(Assignment<Lecture,Placement> assignment)

Description copied from interface: Criterion

Current value of the criterion (optimization objective)

Specified by:

getValue in interface Criterion<Lecture,Placement>

Overrides:

getValue in class AbstractCriterion<Lecture,Placement>

Parameters:

assignment - current assignment

Returns:

value of this criterion

getValue

public double getValue(Assignment<Lecture,Placement> assignment,
                       Collection<Lecture> variables)

Description copied from interface: Criterion

Value of a part of the problem (given by the collection of variables)

Specified by:

getValue in interface Criterion<Lecture,Placement>

Overrides:

getValue in class AbstractCriterion<Lecture,Placement>

Parameters:

assignment - current assignment

variables - list of problem variables

Returns:

value of the given variables

getBounds

public double[] getBounds(Assignment<Lecture,Placement> assignment)

Description copied from interface: Criterion

Bounds (minimum and maximum) estimate for the value

Specified by:

getBounds in interface Criterion<Lecture,Placement>

Overrides:

getBounds in class AbstractCriterion<Lecture,Placement>

Parameters:

assignment - current assignment

Returns:

minimum and maximum of the criterion value

getBounds

public double[] getBounds(Assignment<Lecture,Placement> assignment,
                          Collection<Lecture> variables)

Description copied from interface: Criterion

Value bounds (minimum and maximum) of the criterion on a part of the problem

Specified by:

getBounds in interface Criterion<Lecture,Placement>

Overrides:

getBounds in class AbstractCriterion<Lecture,Placement>

Parameters:

assignment - current assignment

variables - list of problem variables

Returns:

minimum and maximum of this criterion for the given sub-problem