ExamGreatDeluge (Constraint Solver API Documentation -- CPSolver v1.2 build 156)

java.lang.Object
- net.sf.cpsolver.exam.heuristics.ExamGreatDeluge

All Implemented Interfaces:

NeighbourSelection<Exam,ExamPlacement>, LazyNeighbour.LazyNeighbourAcceptanceCriterion<Exam,ExamPlacement>, SolutionListener<Exam,ExamPlacement>
```
public class ExamGreatDeluge
extends Object
implements NeighbourSelection<Exam,ExamPlacement>, SolutionListener<Exam,ExamPlacement>, LazyNeighbour.LazyNeighbourAcceptanceCriterion<Exam,ExamPlacement>
```
Greate deluge. In each iteration, one of the following three neighbourhoods is selected first
- random move (ExamRandomMove)
- period swap (ExamTimeMove)
- room swap (ExamRoomMove)
, then a neighbour is generated and it is accepted if the value of the new solution is below certain bound. This bound is initialized to the GreatDeluge.UpperBoundRate × value of the best solution ever found. After each iteration, the bound is decreased by GreatDeluge.CoolRate (new bound equals to old bound × GreatDeluge.CoolRate). If the bound gets bellow GreatDeluge.LowerBoundRate × value of the best solution ever found, it is changed back to GreatDeluge.UpperBoundRate × value of the best solution ever found. If there was no improvement found between the bounds, the new bounds are changed to GreatDeluge.UpperBoundRate^2 and GreatDeluge.LowerBoundRate^2, GreatDeluge.UpperBoundRate^3 and GreatDeluge.LowerBoundRate^3, etc. till there is an improvement found.
Version:

ExamTT 1.2 (Examination Timetabling)
Copyright (C) 2008 - 2010 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/.

Constructor Summary

Constructors
Constructor and Description

ExamGreatDeluge(DataProperties properties)
Constructor.

Constructors
Constructor and Description
`ExamGreatDeluge(DataProperties properties)` Constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`accept(LazyNeighbour<Exam,ExamPlacement> neighbour, double value)` Accept lazy neighbour
`protected boolean`	`accept(Solution<Exam,ExamPlacement> solution, Neighbour<Exam,ExamPlacement> neighbour)` Accept neighbour
`void`	`bestCleared(Solution<Exam,ExamPlacement> solution)` Called by the solution when method `Solution.clearBest()` is called.
`void`	`bestRestored(Solution<Exam,ExamPlacement> solution)` Called by the solution when method `Solution.restoreBest()` is called.
`void`	`bestSaved(Solution<Exam,ExamPlacement> solution)` Update last improving iteration count
`Neighbour<Exam,ExamPlacement>`	`genMove(Solution<Exam,ExamPlacement> solution)` Generate neighbour -- select neighbourhood randomly, select neighbour
`void`	`getInfo(Solution<Exam,ExamPlacement> solution, Map<String,String> info)` Called by the solution when it is asked to produce info table, see `Solution.getInfo()`.
`void`	`getInfo(Solution<Exam,ExamPlacement> solution, Map<String,String> info, Collection<Exam> variables)` Called by the solution when it is asked to produce info table, see `Solution.getInfo()`.
`protected void`	`incIter(Solution<Exam,ExamPlacement> solution)` Increment iteration count, update bound
`protected void`	`info(Solution<Exam,ExamPlacement> solution)` Print some information
`void`	`init(Solver<Exam,ExamPlacement> solver)` Initialization
`Neighbour<Exam,ExamPlacement>`	`selectNeighbour(Solution<Exam,ExamPlacement> solution)` A neighbour is generated randomly untill an acceptable one is found.
`void`	`solutionUpdated(Solution<Exam,ExamPlacement> solution)` Called by the solution when it is updated, see `Solution.update(double)`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ExamGreatDeluge
```
public ExamGreatDeluge(DataProperties properties)
```
    Constructor. Following problem properties are considered:
    - GreatDeluge.CoolRate ... bound cooling rate (default 0.99999995)
    - GreatDeluge.UpperBoundRate ... bound upper bound relative to best solution ever found (default 1.05)
    - GreatDeluge.LowerBoundRate ... bound lower bound relative to best solution ever found (default 0.95)
    Parameters:
    
    properties - problem properties
- Method Detail
  - init
```
public void init(Solver<Exam,ExamPlacement> solver)
```
    Initialization
    
    Specified by:
    
    init in interface NeighbourSelection<Exam,ExamPlacement>
  - info
```
protected void info(Solution<Exam,ExamPlacement> solution)
```
    Print some information
  - genMove
```
public Neighbour<Exam,ExamPlacement> genMove(Solution<Exam,ExamPlacement> solution)
```
    Generate neighbour -- select neighbourhood randomly, select neighbour
  - accept
```
protected boolean accept(Solution<Exam,ExamPlacement> solution,
                         Neighbour<Exam,ExamPlacement> neighbour)
```
    Accept neighbour
  - accept
```
public boolean accept(LazyNeighbour<Exam,ExamPlacement> neighbour,
                      double value)
```
    Accept lazy neighbour
    
    Specified by:
    
    accept in interface LazyNeighbour.LazyNeighbourAcceptanceCriterion<Exam,ExamPlacement>
    
    Parameters:
    
    neighbour - neighbour that was assigned
    
    value - change in overall solution value
    
    Returns:
    
    true if the neighbour can be accepted (false to undo the assignment)
  - incIter
```
protected void incIter(Solution<Exam,ExamPlacement> solution)
```
    Increment iteration count, update bound
  - selectNeighbour
```
public Neighbour<Exam,ExamPlacement> selectNeighbour(Solution<Exam,ExamPlacement> solution)
```
    A neighbour is generated randomly untill an acceptable one is found.
    
    Specified by:
    
    selectNeighbour in interface NeighbourSelection<Exam,ExamPlacement>
    
    Parameters:
    
    solution - given solution
    
    Returns:
    
    a neighbour assignment
  - bestSaved
```
public void bestSaved(Solution<Exam,ExamPlacement> solution)
```
    Update last improving iteration count
    
    Specified by:
    
    bestSaved in interface SolutionListener<Exam,ExamPlacement>
    
    Parameters:
    
    solution - source solution
  - solutionUpdated
```
public void solutionUpdated(Solution<Exam,ExamPlacement> solution)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when it is updated, see Solution.update(double).
    
    Specified by:
    
    solutionUpdated in interface SolutionListener<Exam,ExamPlacement>
    
    Parameters:
    
    solution - source solution
  - getInfo
```
public void getInfo(Solution<Exam,ExamPlacement> solution,
                    Map<String,String> info)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when it is asked to produce info table, see Solution.getInfo(). A listener can also add some its info into this table.
    
    Specified by:
    
    getInfo in interface SolutionListener<Exam,ExamPlacement>
    
    Parameters:
    
    solution - source solution
    
    info - produced info table
  - getInfo
```
public void getInfo(Solution<Exam,ExamPlacement> solution,
                    Map<String,String> info,
                    Collection<Exam> variables)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when it is asked to produce info table, see Solution.getInfo(). A listener can also add some its info into this table.
    
    Specified by:
    
    getInfo in interface SolutionListener<Exam,ExamPlacement>
    
    Parameters:
    
    solution - source solution
    
    info - produced info table
    
    variables - only variables from this set are included
  - bestCleared
```
public void bestCleared(Solution<Exam,ExamPlacement> solution)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when method Solution.clearBest() is called.
    
    Specified by:
    
    bestCleared in interface SolutionListener<Exam,ExamPlacement>
    
    Parameters:
    
    solution - source solution
  - bestRestored
```
public void bestRestored(Solution<Exam,ExamPlacement> solution)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when method Solution.restoreBest() is called.
    
    Specified by:
    
    bestRestored in interface SolutionListener<Exam,ExamPlacement>
    
    Parameters:
    
    solution - source solution

Class ExamGreatDeluge

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ExamGreatDeluge

Method Detail

init

info

genMove

accept

accept

incIter

selectNeighbour

bestSaved

solutionUpdated

getInfo

getInfo

bestCleared

bestRestored