org.cpsolver.coursett.neighbourhoods

Class RoomSwap

java.lang.Object

org.cpsolver.ifs.algorithms.neighbourhoods.RandomSwapMove<Lecture,Placement>

org.cpsolver.coursett.neighbourhoods.RoomSwap

All Implemented Interfaces:

HillClimberSelection, NeighbourSelection<Lecture,Placement>

public class RoomSwap
extends RandomSwapMove<Lecture,Placement>

Try to assign a class with a new room. A class is selected randomly, a different room is randomly selected for the class -- the class is assigned into the new room. If the room is used or there is some other conflict, it tries to resolve these conflicts by assigning conflicting classes to other rooms as well.

Version:

IFS 1.3 (Iterative Forward Search)
Copyright (C) 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/.

Nested Class Summary

Nested classes/interfaces inherited from class org.cpsolver.ifs.algorithms.neighbourhoods.RandomSwapMove

RandomSwapMove.SwapNeighbour

Field Summary

Fields inherited from class org.cpsolver.ifs.algorithms.neighbourhoods.RandomSwapMove

iHC, iMaxAttempts, iTimeLimit

Constructor Summary

Constructors

Constructor and Description
RoomSwap(DataProperties config)

Method Summary

Modifier and Type	Method and Description
void	init(Solver<Lecture,Placement> solver) Criterion initialization
Double	resolve(Solution<Lecture,Placement> solution, double total, long startTime, Map<Lecture,Placement> assignments, List<Placement> conflicts, int index) Try to resolve given conflicts.
Neighbour<Lecture,Placement>	selectNeighbour(Solution<Lecture,Placement> solution) select a neighbour of a given solution

Methods inherited from class org.cpsolver.ifs.algorithms.neighbourhoods.RandomSwapMove

isTimeLimitReached, setHcMode

Methods inherited from class java.lang.Object

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

Constructor Detail

RoomSwap

public RoomSwap(DataProperties config)

Method Detail

init

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

Description copied from interface: NeighbourSelection

Criterion initialization

Specified by:

init in interface NeighbourSelection<Lecture,Placement>

Overrides:

init in class RandomSwapMove<Lecture,Placement>

Parameters:

solver - current solver

selectNeighbour

public Neighbour<Lecture,Placement> selectNeighbour(Solution<Lecture,Placement> solution)

Description copied from interface: NeighbourSelection

select a neighbour of a given solution

Specified by:

selectNeighbour in interface NeighbourSelection<Lecture,Placement>

Overrides:

selectNeighbour in class RandomSwapMove<Lecture,Placement>

Parameters:

solution - given solution

Returns:

a neighbour assignment

resolve

public Double resolve(Solution<Lecture,Placement> solution,
                      double total,
                      long startTime,
                      Map<Lecture,Placement> assignments,
                      List<Placement> conflicts,
                      int index)

Description copied from class: RandomSwapMove

Try to resolve given conflicts. For each conflicting variable it tries to find a value with no conflict that is compatible with some other assignment of the other conflicting variables.

Overrides:

resolve in class RandomSwapMove<Lecture,Placement>

Parameters:

solution - current solution

total - original value of the current solution

startTime - starting time

assignments - re-assignments to be made

conflicts - list of conflicts to resolve

index - index in the list of conflicts

Returns:

value of the modified solution, null if cannot be resolved