gov.sns.tools.optimization
Class RandomSearchAlgorithm.RandomSearcher

java.lang.Object
  |
  +--gov.sns.tools.optimization.RandomSearchAlgorithm.RandomSearcher

All Implemented Interfaces:

RandomSearchAlgorithm.Searcher, gov.sns.tools.optimization.ScoreMonitor

Direct Known Subclasses:

RandomSearchAlgorithm.ComboSearcher, RandomSearchAlgorithm.ShrinkSearcher

Enclosing class:

RandomSearchAlgorithm

protected class RandomSearchAlgorithm.RandomSearcher

extends java.lang.Object

implements RandomSearchAlgorithm.Searcher

A searcher that performs a simple random search in the entire search space.

Field Summary

protected double	changeProbabilityBase
protected java.util.Random	randomGenerator
protected java.util.Map	values

Constructor Summary

RandomSearchAlgorithm.RandomSearcher()
Constructor

Method Summary

void	newScore(java.lang.Object sender, Solution solution) Notifies the receiver of a new score event.
void	newTopSolution(TrialPoint oldPoint, TrialPoint newPoint) An event indicating that a new solution has been found which is better than the previous best solution according to the score given by the evaluator.
TrialPoint	nextPoint() Get the next trial point.
TrialPoint	nextPoint(int expectedNumToChange) Get the next trial point given the expected number of variables to change.
TrialPoint	nextTrialPoint() Get the next trial point.
protected double	proposeValue(Variable variable) Propose a new value for the variable by selecting a random value in the variable's search range.
void	reset() reset for searching from scratch; forget history

Methods inherited from class java.lang.Object

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

Field Detail

randomGenerator

protected java.util.Random randomGenerator

changeProbabilityBase

protected double changeProbabilityBase

values

protected java.util.Map values

Constructor Detail

RandomSearchAlgorithm.RandomSearcher

public RandomSearchAlgorithm.RandomSearcher()

Constructor

Method Detail

reset

public void reset()

reset for searching from scratch; forget history

Specified by:

reset in interface RandomSearchAlgorithm.Searcher

newTopSolution

public void newTopSolution(TrialPoint oldPoint,
                           TrialPoint newPoint)

An event indicating that a new solution has been found which is better than the previous best solution according to the score given by the evaluator.

Specified by:

newTopSolution in interface RandomSearchAlgorithm.Searcher

Parameters:

oldPoint - The old best point.

newPoint - The new best point.

nextTrialPoint

public TrialPoint nextTrialPoint()

Get the next trial point. Simply returns nextPoint().

Specified by:

nextTrialPoint in interface RandomSearchAlgorithm.Searcher

Returns:

the next trial point.

nextPoint

public TrialPoint nextPoint()

Get the next trial point.

Returns:

the next trial point.

nextPoint

public TrialPoint nextPoint(int expectedNumToChange)

Get the next trial point given the expected number of variables to change. Randomly pick the number of variables to vary by weighting it based on the average number we expect to vary. If no variables get selected to change then we pick the number of variables to change randomly from 1 to the total number of variables available. For each variable that was selected to change, we randomly select a value within the target domain for the variable.

Parameters:

expectedNumToChange - The average number of variables that we expect to change.

Returns:

the next trial point.

proposeValue

protected double proposeValue(Variable variable)

Propose a new value for the variable by selecting a random value in the variable's search range.

Parameters:

variable - the variable for which to propose a new value

Returns:

the new value to propose for the variable

newScore

public void newScore(java.lang.Object sender,
                     Solution solution)

Notifies the receiver of a new score event.

Specified by:

newScore in interface gov.sns.tools.optimization.ScoreMonitor

Parameters:

sender - The object posting the event.

solution - The solution posted.