org.cpsolver.coursett.heuristics

Class FixCompleteSolutionNeighbourSelection

java.lang.Object

org.cpsolver.ifs.assignment.context.NeighbourSelectionWithContext<Lecture,Placement,FixCompleteSolutionNeighbourSelection.FixCompleteSolutionNeighbourContext>

org.cpsolver.coursett.heuristics.FixCompleteSolutionNeighbourSelection

All Implemented Interfaces:

CanHoldContext, HasAssignmentContext<Lecture,Placement,FixCompleteSolutionNeighbourSelection.FixCompleteSolutionNeighbourContext>, NeighbourSelection<Lecture,Placement>

public class FixCompleteSolutionNeighbourSelection
extends NeighbourSelectionWithContext<Lecture,Placement,FixCompleteSolutionNeighbourSelection.FixCompleteSolutionNeighbourContext>

University course timetabling neighbour selection.

When a complete solution is found, it is improved by limited depth backtracking search. This way it is ensured that the fund solution is at least locally optimal.

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

Modifier and Type	Class and Description
class	FixCompleteSolutionNeighbourSelection.FixCompleteSolutionNeighbourContext

Field Summary

Fields inherited from class org.cpsolver.ifs.assignment.context.NeighbourSelectionWithContext

iContextOverride

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

sMaxSize

Constructor Summary

Constructors

Constructor and Description
FixCompleteSolutionNeighbourSelection(DataProperties config)
FixCompleteSolutionNeighbourSelection(DataProperties config, NeighbourSelection<Lecture,Placement> parent)

Method Summary

Modifier and Type	Method and Description
FixCompleteSolutionNeighbourSelection.FixCompleteSolutionNeighbourContext	createAssignmentContext(Assignment<Lecture,Placement> assignment) Create a new assignment context for the given assignment.
void	init(Solver<Lecture,Placement> solver) Criterion initialization
Neighbour<Lecture,Placement>	selectNeighbour(Solution<Lecture,Placement> solution) Try to improve existing solution by backtracking search of very limited depth.

Methods inherited from class org.cpsolver.ifs.assignment.context.NeighbourSelectionWithContext

getAssignmentContextReference, getContext, getContext, hasContextOverride, isSingleContextSolver, setAssignmentContextReference

Methods inherited from class java.lang.Object

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

Constructor Detail

FixCompleteSolutionNeighbourSelection

public FixCompleteSolutionNeighbourSelection(DataProperties config,
                                             NeighbourSelection<Lecture,Placement> parent)
                                      throws Exception

Throws:

Exception

FixCompleteSolutionNeighbourSelection

public FixCompleteSolutionNeighbourSelection(DataProperties config)
                                      throws Exception

Throws:

Exception

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 NeighbourSelectionWithContext<Lecture,Placement,FixCompleteSolutionNeighbourSelection.FixCompleteSolutionNeighbourContext>

Parameters:

solver - current solver

selectNeighbour

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

Try to improve existing solution by backtracking search of very limited depth. See NeighbourSelectionWithSuggestions for more details.

Parameters:

solution - given solution

Returns:

a neighbour assignment

createAssignmentContext

public FixCompleteSolutionNeighbourSelection.FixCompleteSolutionNeighbourContext createAssignmentContext(Assignment<Lecture,Placement> assignment)

Description copied from interface: HasAssignmentContext

Create a new assignment context for the given assignment. If there are already some variables assigned in the value, the method should make sure that the context is appropriately initialized.

Parameters:

assignment - an assignment for which there needs to be an assignment context

Returns:

a new instance of the assignment context, filled according to the given assignment