org.cpsolver.studentsct.heuristics.selection

Class OnlineSelection

java.lang.Object

org.cpsolver.studentsct.heuristics.selection.BranchBoundSelection

org.cpsolver.studentsct.heuristics.selection.OnlineSelection

All Implemented Interfaces:

NeighbourSelection<Request,Enrollment>, InfoProvider<Request,Enrollment>, SolverListener<Request,Enrollment>

public class OnlineSelection
extends BranchBoundSelection

Section given student using branch & bound algorithm with no unassignments allowed.

Parameters:

Related Solver Parameters

Parameter	Type	Comment
Sectioning.UseStudentPreferencePenalties	Boolean	If true, StudentPreferencePenalties are used
Sectioning.Distribution	Integer	When student preference penalties are used, defines which distribution is to be used (one of StudentPreferencePenalties.sDistTypePreference, StudentPreferencePenalties.sDistTypePreferenceQuadratic, StudentPreferencePenalties.sDistTypePreferenceReverse, StudentPreferencePenalties.sDistTypeUniform)
Sectioning.UseOnlinePenalties	Boolean	If true, online sectioning penalties computed based on held/expected space are used.
Sectioning.Epsilon	Double	When both online penalties and student preference penalties are used: a solution based on online penalties is computed first, this solution (and the given epsilon) is then used to setup bounds on online penalties for the solution that minimizes student preference penalties. Limit on online penalty is computed as (1+Section.Epsilon) BranchBoundSelection.Selection.getPenalty(), i.e., only sections with penalty equal or below this limit can be used -- among these the solution that minimizes student preference penalties is computed.

Version:

StudentSct 1.3 (Student Sectioning)
Copyright (C) 2007 - 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	OnlineSelection.EpsilonSelection Branch & bound selection for a student

Nested classes/interfaces inherited from class org.cpsolver.studentsct.heuristics.selection.BranchBoundSelection

BranchBoundSelection.BranchBoundNeighbour, BranchBoundSelection.Selection

Field Summary

Fields inherited from class org.cpsolver.studentsct.heuristics.selection.BranchBoundSelection

iBranchWhenSelectedHasNoConflict, iDistanceConflict, iDistConfWeight, iFilter, iMinimizePenalty, iModel, iNbrIterations, iNbrNoSolution, iNbrStudents, iNbrTimeoutReached, iOrder, iStudentQuality, iStudents, iTimeout, iTimeOverlaps, iTimesToAvoidHeuristics, iTotalTime, sDebug

Constructor Summary

Constructors

Constructor and Description
OnlineSelection(DataProperties properties) Constructor

Method Summary

Modifier and Type	Method and Description
BranchBoundSelection.Selection	getSelection(Assignment<Request,Enrollment> assignment, Student student) Branch & bound selection for a student
void	init(Solver<Request,Enrollment> solver) Criterion initialization
boolean	isUsePenalties() Use online penalties
boolean	isUseStudentPrefPenalties() Use student preference penalties
void	updateSpace(Assignment<Request,Enrollment> assignment, Student student) Update online sectioning info after the given student is sectioned

Methods inherited from class org.cpsolver.studentsct.heuristics.selection.BranchBoundSelection

addStudent, getFilter, getInfo, getInfo, init, neighbourFailed, neighbourSelected, nextStudent, selectNeighbour, setModel, valueSelected, variableSelected, withFilter

Methods inherited from class java.lang.Object

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

Constructor Detail

OnlineSelection

public OnlineSelection(DataProperties properties)

Constructor

Parameters:

properties - configuration

Method Detail

init

public void init(Solver<Request,Enrollment> solver)

Description copied from interface: NeighbourSelection

Criterion initialization

Specified by:

init in interface NeighbourSelection<Request,Enrollment>

Overrides:

init in class BranchBoundSelection

Parameters:

solver - current solver

isUseStudentPrefPenalties

public boolean isUseStudentPrefPenalties()

Use student preference penalties

Returns:

true if student preference penalties are to be used

isUsePenalties

public boolean isUsePenalties()

Use online penalties

Returns:

true if online penalties are to be used

updateSpace

public void updateSpace(Assignment<Request,Enrollment> assignment,
                        Student student)

Update online sectioning info after the given student is sectioned

Parameters:

assignment - current assignment

student - student in question

getSelection

public BranchBoundSelection.Selection getSelection(Assignment<Request,Enrollment> assignment,
                                                   Student student)

Branch & bound selection for a student

Overrides:

getSelection in class BranchBoundSelection

Parameters:

assignment - current assignment

student - selected student

Returns:

selection