MaxIdleNeighbourSelection (Constraint Solver API Documentation -- CPSolver v1.4 build 81)

java.lang.Object
- org.cpsolver.ifs.assignment.context.NeighbourSelectionWithContext<V,T,MaxIdleNeighbourSelection.MaxIdleContext>
- - org.cpsolver.ifs.heuristics.MaxIdleNeighbourSelection<V,T>

Type Parameters:

V - Variable

T - Value

All Implemented Interfaces:

CanHoldContext, HasAssignmentContext<V,T,MaxIdleNeighbourSelection.MaxIdleContext>, NeighbourSelection<V,T>, SolutionListener<V,T>
```
public class MaxIdleNeighbourSelection<V extends Variable<V,T>,T extends Value<V,T>>
extends NeighbourSelectionWithContext<V,T,MaxIdleNeighbourSelection.MaxIdleContext>
implements SolutionListener<V,T>
```
Simple extension of a provided NeighbourSelection that halts the construction heuristic or the IFS search when the underlying heuristic is unable to improve the number of assigned variables. When a given number of non-improving iterations is reached, the MaxIdleNeighbourSelection extension starts returning null. The counter gets automatically reset every time a solution with more variables assigned is stored as best solution.

Version:

IFS 1.4 (Iterative Forward Search)
Copyright (C) 2024 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

See Also:

NeighbourSelection

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

class MaxIdleNeighbourSelection.MaxIdleContext

Nested Classes
Modifier and Type	Class and Description
`class`	`MaxIdleNeighbourSelection.MaxIdleContext`

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`iBestAssigned`
`protected int`	`iMaxIdle`
`protected NeighbourSelection<V,T>`	`iParent`
`protected ConflictStatistics<V,T>`	`iStat`
`protected long`	`iTimeOut`

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
`MaxIdleNeighbourSelection(DataProperties properties, NeighbourSelection<V,T> parent, int maxIdle)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`bestCleared(Solution<V,T> solution)` Called by the solution when method `Solution.clearBest()` is called.
`void`	`bestRestored(Solution<V,T> solution)` Called by the solution when method `Solution.restoreBest()` is called.
`void`	`bestSaved(Solution<V,T> solution)` Called by the solution when method `Solution.saveBest()` is called.
`MaxIdleNeighbourSelection.MaxIdleContext`	`createAssignmentContext(Assignment<V,T> assignment)` Create a new assignment context for the given assignment.
`void`	`getInfo(Solution<V,T> solution, Map<String,String> info)` Called by the solution when it is asked to produce info table, see `Solution.getInfo()`.
`void`	`getInfo(Solution<V,T> solution, Map<String,String> info, Collection<V> variables)` Called by the solution when it is asked to produce info table, see `Solution.getInfo()`.
`void`	`init(Solver<V,T> solver)` Criterion initialization
`Neighbour<V,T>`	`selectNeighbour(Solution<V,T> solution)` select a neighbour of a given solution
`void`	`solutionUpdated(Solution<V,T> solution)` Called by the solution when it is updated, see `Solution.update(double)`.

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

- Field Detail
  - iParent
```
protected NeighbourSelection<V extends Variable<V,T>,T extends Value<V,T>> iParent
```
  - iMaxIdle
```
protected int iMaxIdle
```
  - iBestAssigned
```
protected int iBestAssigned
```
  - iStat
```
protected ConflictStatistics<V extends Variable<V,T>,T extends Value<V,T>> iStat
```
  - iTimeOut
```
protected long iTimeOut
```
- Constructor Detail
  - MaxIdleNeighbourSelection
```
public MaxIdleNeighbourSelection(DataProperties properties,
                                 NeighbourSelection<V,T> parent,
                                 int maxIdle)
```
- Method Detail
  - init
```
public void init(Solver<V,T> solver)
```
    Description copied from interface: NeighbourSelection
    
    Criterion initialization
    
    Specified by:
    
    init in interface NeighbourSelection<V extends Variable<V,T>,T extends Value<V,T>>
    
    Overrides:
    
    init in class NeighbourSelectionWithContext<V extends Variable<V,T>,T extends Value<V,T>,MaxIdleNeighbourSelection.MaxIdleContext>
    
    Parameters:
    
    solver - current solver
  - solutionUpdated
```
public void solutionUpdated(Solution<V,T> solution)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when it is updated, see Solution.update(double).
    
    Specified by:
    
    solutionUpdated in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>
    
    Parameters:
    
    solution - source solution
  - getInfo
```
public void getInfo(Solution<V,T> 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<V extends Variable<V,T>,T extends Value<V,T>>
    
    Parameters:
    
    solution - source solution
    
    info - produced info table
  - getInfo
```
public void getInfo(Solution<V,T> solution,
                    Map<String,String> info,
                    Collection<V> 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<V extends Variable<V,T>,T extends Value<V,T>>
    
    Parameters:
    
    solution - source solution
    
    info - produced info table
    
    variables - only variables from this set are included
  - bestCleared
```
public void bestCleared(Solution<V,T> solution)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when method Solution.clearBest() is called.
    
    Specified by:
    
    bestCleared in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>
    
    Parameters:
    
    solution - source solution
  - bestSaved
```
public void bestSaved(Solution<V,T> solution)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when method Solution.saveBest() is called.
    
    Specified by:
    
    bestSaved in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>
    
    Parameters:
    
    solution - source solution
  - bestRestored
```
public void bestRestored(Solution<V,T> solution)
```
    Description copied from interface: SolutionListener
    
    Called by the solution when method Solution.restoreBest() is called.
    
    Specified by:
    
    bestRestored in interface SolutionListener<V extends Variable<V,T>,T extends Value<V,T>>
    
    Parameters:
    
    solution - source solution
  - selectNeighbour
```
public Neighbour<V,T> selectNeighbour(Solution<V,T> solution)
```
    Description copied from interface: NeighbourSelection
    
    select a neighbour of a given solution
    
    Specified by:
    
    selectNeighbour in interface NeighbourSelection<V extends Variable<V,T>,T extends Value<V,T>>
    
    Parameters:
    
    solution - given solution
    
    Returns:
    
    a neighbour assignment
  - createAssignmentContext
```
public MaxIdleNeighbourSelection.MaxIdleContext createAssignmentContext(Assignment<V,T> 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.
    
    Specified by:
    
    createAssignmentContext in interface HasAssignmentContext<V extends Variable<V,T>,T extends Value<V,T>,MaxIdleNeighbourSelection.MaxIdleContext>
    
    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

Class MaxIdleNeighbourSelection<V extends Variable<V,T>,T extends Value<V,T>>

Nested Class Summary

Field Summary

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

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

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Field Detail

iParent

iMaxIdle

iBestAssigned

iStat

iTimeOut

Constructor Detail

MaxIdleNeighbourSelection

Method Detail

init

solutionUpdated

getInfo

getInfo

bestCleared

bestSaved

bestRestored

selectNeighbour

createAssignmentContext