org.omegahat.Numerics.Optimizers
Class LineSearchBasic

java.lang.Object
  |
  +--org.omegahat.Numerics.Optimizers.LineSearchBasic

All Implemented Interfaces:

LineSearch

Direct Known Subclasses:

LineSearchWolfe

public abstract class LineSearchBasic

extends java.lang.Object

implements LineSearch

the basic line search algorithm structure, without any particular algorithm.

This class defines some fields, such as the minimum and maximum step length, plus a few utility methods.

Field Summary

protected boolean	debug
protected NumericArray	direction
protected int	evaluations the number of evaluations in this line search.
protected int	maxEvaluations
protected LineStep	origin
protected int	state the state represented by this step.
protected double	stepMax steps must never be greater than this (large) number, default 1.e20.
protected double	stepMin steps must never be less than this (small) number, default 1e-20.

Fields inherited from interface org.omegahat.Numerics.Optimizers.LineSearch

CONTINUE, EXCEPTION, SUCCESSFUL, TOO_LARGE, TOO_MANY, TOO_NARROW, TOO_SMALL

Constructor Summary

LineSearchBasic()

Method Summary

boolean	continueIteration(LineStep step) Tests whether the search should continue.
boolean	getDebug() Accessor for debug field
NumericArray	getDirection() Accessor for direction field
int	getEvaluations() Accessor for evaluations field
int	getMaxEvaluations() Accessor for maxEvaluations field
LineStep	getOrigin() Accessor for origin field
int	getState() Accessor for state field
double	getStepMax() Accessor for stepMax field
double	getStepMin() Accessor for stepMin field
int	incrementCount() Increment the count of evaluations; this does not test against the maxEvaluations field, but the continueIteration method should.
LineStep	initialize(ModelPointNumericInt origin, NumericArray p, double step) Initialize the original step using the given model point, direction and step size.
boolean	setDebug(boolean value) Accessor for setting debug field
NumericArray	setDirection(NumericArray value) Accessor for setting direction field
int	setEvaluations(int value) Accessor for setting evaluations field
int	setMaxEvaluations(int value) Accessor for setting maxEvaluations field
LineStep	setOrigin(LineStep value) Accessor for setting origin field
int	setState(int value) Accessor for setting state field
double	setStepMax(double value) Accessor for setting stepMax field
double	setStepMin(double value) Accessor for setting stepMin field

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.omegahat.Numerics.Optimizers.LineSearch

refineStep

Field Detail

evaluations

protected int evaluations

the number of evaluations in this line search.

maxEvaluations

protected int maxEvaluations

state

protected int state

the state represented by this step.

It should be one of the pre-defined states in the LineSearch interface.

stepMax

protected double stepMax

steps must never be greater than this (large) number, default 1.e20.

stepMin

protected double stepMin

steps must never be less than this (small) number, default 1e-20.

origin

protected LineStep origin

direction

protected NumericArray direction

debug

protected boolean debug

Constructor Detail

LineSearchBasic

public LineSearchBasic()

Method Detail

getEvaluations

public int getEvaluations()

Accessor for evaluations field

setEvaluations

public int setEvaluations(int value)

Accessor for setting evaluations field

getMaxEvaluations

public int getMaxEvaluations()

Accessor for maxEvaluations field

setMaxEvaluations

public int setMaxEvaluations(int value)

Accessor for setting maxEvaluations field

getState

public int getState()

Accessor for state field

Specified by:

getState in interface LineSearch

setState

public int setState(int value)

Accessor for setting state field

Specified by:

setState in interface LineSearch

getStepMax

public double getStepMax()

Accessor for stepMax field

setStepMax

public double setStepMax(double value)

Accessor for setting stepMax field

getStepMin

public double getStepMin()

Accessor for stepMin field

setStepMin

public double setStepMin(double value)

Accessor for setting stepMin field

getOrigin

public LineStep getOrigin()

Accessor for origin field

setOrigin

public LineStep setOrigin(LineStep value)

Accessor for setting origin field

getDirection

public NumericArray getDirection()

Accessor for direction field

setDirection

public NumericArray setDirection(NumericArray value)

Accessor for setting direction field

getDebug

public boolean getDebug()

Accessor for debug field

setDebug

public boolean setDebug(boolean value)

Accessor for setting debug field

incrementCount

public int incrementCount()

Increment the count of evaluations; this does not test against the maxEvaluations field, but the continueIteration method should.

initialize

public LineStep initialize(ModelPointNumericInt origin,
                           NumericArray p,
                           double step)

Initialize the original step using the given model point, direction and step size.

The returned object has an (unevaluated) model point shifted by the specified step along the specified direction from the origin.

Specified by:

initialize in interface LineSearch

continueIteration

public boolean continueIteration(LineStep step)

Tests whether the search should continue. If not, sets the internal state to a non-zero value, e.g., SUCCESSFUL in case of numeric convergence by the criterion of the search, or any of a number of states indicating failure.

The method in this class only checks for failures: too small or large a step, or too many evaluations.

Specified by:

continueIteration in interface LineSearch