xal.extension.solver.algorithm

Class DirectedStep

java.lang.Object

xal.extension.solver.algorithm.SearchAlgorithm

xal.extension.solver.algorithm.DirectedStep

All Implemented Interfaces:

AlgorithmScheduleListener, SolutionJudgeListener

public class DirectedStep
extends SearchAlgorithm

Based on the acceleration-step of Forsythe and Motzkin

Field Summary

Fields inherited from class xal.extension.solver.algorithm.SearchAlgorithm

_eventProxy, _messageCenter, _problem

Constructor Summary

Constructors

Constructor and Description
DirectedStep() Constructor

Method Summary

Modifier and Type	Method and Description
void	algorithmAvailable(SearchAlgorithm source) Handle a message that an algorithm is available.
void	algorithmUnavailable(SearchAlgorithm source) Handle a message that an algorithm is not available.
protected double[]	calculateGradient(Trial originTrial, AlgorithmRun algorithmRun) Calculate the gradient for the specified point
protected double[]	calculateVector(TrialPoint originPoint, TrialPoint targetPoint) Calculate the vector from the origin point to the target point
void	foundNewOptimalSolution(SolutionJudge source, java.util.List<Trial> solutions, Trial solution) Handle a message that a new optimal solution has been found.
java.lang.String	getLabel() Return the label for a search algorithm.
int	getMinEvaluationsPerRun() Get the minimum number of evaluations per run.
int	globalRating() Returns the global rating which in an integer between 0 and 10.
int	localRating() Returns the local rating which is an integer between 0 and 10.
protected Trial	performAcceleratedSearch(Trial originTrial, AlgorithmRun algorithmRun) Perform an accelerated search.
protected Trial	performGradientAndLinearSearch(Trial originTrial, AlgorithmRun algorithmRun) Perform a gradient calculation followed by a linear search along the gradient.
void	performRun(AlgorithmRun algorithmRun) Calculate the next few trial points.
void	reset() reset the algorithm for searching from scratch
protected Trial	searchAlongGradient(double[] gradient, Trial originTrial, AlgorithmRun algorithmRun) Search along the gradient from the origin point.
protected static TrialPoint	trialPointAlongGradient(double[] gradient, TrialPoint originPoint, double scale, java.util.List<Variable> variables) Get a new trial point along the gradient.
void	trialScored(AlgorithmSchedule schedule, Trial trial) Handle a message that a trial has been scored.
void	trialVetoed(AlgorithmSchedule schedule, Trial trial) Handle a message that a trial has been vetoed.

Methods inherited from class xal.extension.solver.algorithm.SearchAlgorithm

addSearchAlgorithmListener, getMaxEvaluationsPerRun, removeSearchAlgorithmListener, setProblem, strategyExecuted, strategyWillExecute

Methods inherited from class java.lang.Object

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

Constructor Detail

DirectedStep

public DirectedStep()

Constructor

Method Detail

reset

public void reset()

reset the algorithm for searching from scratch

Overrides:

reset in class SearchAlgorithm

getLabel

public java.lang.String getLabel()

Return the label for a search algorithm.

Specified by:

getLabel in class SearchAlgorithm

Returns:

The trial point.

performRun

public void performRun(AlgorithmRun algorithmRun)

Calculate the next few trial points.

Specified by:

performRun in class SearchAlgorithm

Parameters:

algorithmRun - the algorithm run to perform the evaluation

performAcceleratedSearch

protected Trial performAcceleratedSearch(Trial originTrial,
                                         AlgorithmRun algorithmRun)

Perform an accelerated search.

performGradientAndLinearSearch

protected Trial performGradientAndLinearSearch(Trial originTrial,
                                               AlgorithmRun algorithmRun)

Perform a gradient calculation followed by a linear search along the gradient.

calculateGradient

protected double[] calculateGradient(Trial originTrial,
                                     AlgorithmRun algorithmRun)

Calculate the gradient for the specified point

Returns:

the gradient at the specified point

calculateVector

protected double[] calculateVector(TrialPoint originPoint,
                                   TrialPoint targetPoint)

Calculate the vector from the origin point to the target point

Returns:

the vector from the origin point to the target point

searchAlongGradient

protected Trial searchAlongGradient(double[] gradient,
                                    Trial originTrial,
                                    AlgorithmRun algorithmRun)

Search along the gradient from the origin point.

trialPointAlongGradient

protected static TrialPoint trialPointAlongGradient(double[] gradient,
                                                    TrialPoint originPoint,
                                                    double scale,
                                                    java.util.List<Variable> variables)

Get a new trial point along the gradient.

getMinEvaluationsPerRun

public int getMinEvaluationsPerRun()

Get the minimum number of evaluations per run. Subclasses may want to override this method.

Overrides:

getMinEvaluationsPerRun in class SearchAlgorithm

Returns:

the minimum number of evaluation per run.

globalRating

public int globalRating()

Returns the global rating which in an integer between 0 and 10.

Returns:

The global rating for this algorithm.

localRating

public int localRating()

Returns the local rating which is an integer between 0 and 10.

Returns:

The local rating for this algorithm.

algorithmAvailable

public void algorithmAvailable(SearchAlgorithm source)

Handle a message that an algorithm is available.

Parameters:

source - The source of the available algorithm.

algorithmUnavailable

public void algorithmUnavailable(SearchAlgorithm source)

Handle a message that an algorithm is not available.

Parameters:

source - The source of the available algorithm.

trialScored

public void trialScored(AlgorithmSchedule schedule,
                        Trial trial)

Handle a message that a trial has been scored.

Specified by:

trialScored in interface AlgorithmScheduleListener

Overrides:

trialScored in class SearchAlgorithm

Parameters:

trial - The trial that was scored.

schedule - the schedule providing this event

trialVetoed

public void trialVetoed(AlgorithmSchedule schedule,
                        Trial trial)

Handle a message that a trial has been vetoed.

Specified by:

trialVetoed in interface AlgorithmScheduleListener

Overrides:

trialVetoed in class SearchAlgorithm

Parameters:

trial - The trial that was vetoed.

schedule - the schedule providing this event

foundNewOptimalSolution

public void foundNewOptimalSolution(SolutionJudge source,
                                    java.util.List<Trial> solutions,
                                    Trial solution)

Handle a message that a new optimal solution has been found.

Specified by:

foundNewOptimalSolution in interface SolutionJudgeListener

Overrides:

foundNewOptimalSolution in class SearchAlgorithm

Parameters:

source - The source of the new optimal solution.

solutions - The list of solutions.

solution - The new optimal solution.