gov.sandia.cognition.learning.algorithm.minimization.line.interpolator

Class LineBracketInterpolatorBrent

java.lang.Object

gov.sandia.cognition.util.AbstractCloneableSerializable

gov.sandia.cognition.learning.algorithm.minimization.line.interpolator.AbstractLineBracketInterpolator<Evaluator<java.lang.Double,java.lang.Double>>

gov.sandia.cognition.learning.algorithm.minimization.line.interpolator.LineBracketInterpolatorBrent

All Implemented Interfaces:

LineBracketInterpolator<Evaluator<java.lang.Double,java.lang.Double>>, CloneableSerializable, java.io.Serializable, java.lang.Cloneable

public class LineBracketInterpolatorBrent
extends AbstractLineBracketInterpolator<Evaluator<java.lang.Double,java.lang.Double>>

Implements Brent's method of function interpolation to find a minimum. If the function is well behaved, then Brent uses non-slope-based parabolic interpolation. Otherwise, Brent uses Golden-section and secant interpolation.

Since:

2.1

Author:

Kevin R. Dixon

See Also:

Serialized Form

Field Summary

Fields inherited from class gov.sandia.cognition.learning.algorithm.minimization.line.interpolator.AbstractLineBracketInterpolator

DEFAULT_TOLERANCE

Constructor Summary

Constructors

Constructor and Description
LineBracketInterpolatorBrent() Creates a new instance of LineBracketInterpolatorBrent

Method Summary

Modifier and Type	Method and Description
double	findMinimum(LineBracket bracket, double minx, double maxx, Evaluator<java.lang.Double,java.lang.Double> function) Finds the minimum of the bracket using the interpolation/extrapolation routine, where the minimum must lie between the minx and maxx values on the x-axis.
LineBracketInterpolatorGoldenSection	getGoldenInterpolator() Getter for goldenInterpolator
LineBracketInterpolatorParabola	getParabolicInterpolator() Getter for parabolicInterpolator
boolean	hasSufficientPoints(LineBracket bracket) Determines if the LineBracket contains a sufficient number/quality of points to conduct the interpolation.
void	setGoldenInterpolator(LineBracketInterpolatorGoldenSection goldenInterpolator) Setter for goldenInterpolator
void	setParabolicInterpolator(LineBracketInterpolatorParabola parabolicInterpolator) Setter for parabolicInterpolator

Methods inherited from class gov.sandia.cognition.learning.algorithm.minimization.line.interpolator.AbstractLineBracketInterpolator

getTolerance, setTolerance

Methods inherited from class gov.sandia.cognition.util.AbstractCloneableSerializable

clone

Methods inherited from class java.lang.Object

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

Methods inherited from interface gov.sandia.cognition.util.CloneableSerializable

clone

Constructor Detail

LineBracketInterpolatorBrent

public LineBracketInterpolatorBrent()

Creates a new instance of LineBracketInterpolatorBrent

Method Detail

findMinimum

public double findMinimum(LineBracket bracket,
                          double minx,
                          double maxx,
                          Evaluator<java.lang.Double,java.lang.Double> function)

Description copied from interface: LineBracketInterpolator

Finds the minimum of the bracket using the interpolation/extrapolation routine, where the minimum must lie between the minx and maxx values on the x-axis.

Parameters:

bracket - Bracket of points

minx - Minimum x-axis value to search for the minimum

maxx - Maximum x-axis value to search for the minimum

function - Function to consider. The function, or gradient, may be evaluated to generate enough output/slope samples to interpolate.

Returns:

Minimum value of the function between minx and maxx.

hasSufficientPoints

public boolean hasSufficientPoints(LineBracket bracket)

Description copied from interface: LineBracketInterpolator

Determines if the LineBracket contains a sufficient number/quality of points to conduct the interpolation.

Parameters:

bracket - LineBracket to consider

Returns:

true if the LineBracket has a sufficient number of points, false if the LineBracket doesn't have enough.

getParabolicInterpolator

public LineBracketInterpolatorParabola getParabolicInterpolator()

Getter for parabolicInterpolator

Returns:

Non-slope based parabolic interpolator.

setParabolicInterpolator

public void setParabolicInterpolator(LineBracketInterpolatorParabola parabolicInterpolator)

Setter for parabolicInterpolator

Parameters:

parabolicInterpolator - Non-slope based parabolic interpolator.

getGoldenInterpolator

public LineBracketInterpolatorGoldenSection getGoldenInterpolator()

Getter for goldenInterpolator

Returns:

Golden-section step interpolator.

setGoldenInterpolator

public void setGoldenInterpolator(LineBracketInterpolatorGoldenSection goldenInterpolator)

Setter for goldenInterpolator

Parameters:

goldenInterpolator - Golden-section step interpolator.