org.josef.science.math

Class Bisection

java.lang.Object

org.josef.science.math.AbstractRootFinder

org.josef.science.math.Bisection

All Implemented Interfaces:

RootFinderStrategy

@Status(stage=PRODUCTION,
        unitTests=COMPLETE)
 @Review(by="Kees Schotanus",
        at="2009-09-28")
public final class Bisection
extends AbstractRootFinder
implements RootFinderStrategy

Finds the roots of a function within a defined interval, using the Bisection method.
To find the root of a function f , f should at least be continuous.
More information on this topic can be found in the WikiPedia by clicking here or on MathWorld by clicking here.

Version:

1.0 $Revision: 5785 $

Author:

Kees Schotanus

Constructor Summary

Constructors

Constructor and Description
Bisection(double accuracy) Creates this Bisection root finder using the supplied accuracy.
Bisection(int iterations) Creates this Bisection root finder using the supplied number of iterations.

Method Summary

Modifier and Type	Method and Description
double	findRoot(SingleParameterFunction function, double left, double right) Finds a root of the supplied function within the supplied interval [left, right] using the Bisection method.

Methods inherited from class org.josef.science.math.AbstractRootFinder

getAccuracy, getInterval, getIterations, setAccuracy, setInterval, setIterations

Methods inherited from class java.lang.Object

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

Constructor Detail

Bisection

public Bisection(int iterations)

Creates this Bisection root finder using the supplied number of iterations.

Parameters:

iterations - The maximum number of iterations to find a root.

Throws:

IllegalArgumentException - When the supplied iterations <= 0.

Bisection

public Bisection(double accuracy)

Creates this Bisection root finder using the supplied accuracy.

Parameters:

accuracy - The accuracy of the found root.

Throws:

IllegalArgumentException - When the supplied accuracy <= 0.

Method Detail

findRoot

public double findRoot(SingleParameterFunction function,
                       double left,
                       double right)

Finds a root of the supplied function within the supplied interval [left, right] using the Bisection method.

Specified by:

findRoot in interface RootFinderStrategy

Parameters:

function - The function for which a root should be found.

left - x value of the left side of the interval.
The y value, that is the value of function(left) should have a sign that is opposite to that of function(right).

right - x value of the right side of the interval.
The y value, that is the value of function(right) should have a sign that is opposite to that of function(left).

Returns:

A root of the supplied function within the supplied interval[ left, right].

Throws:

IllegalArgumentException - When left equals right or when both function(left) and function(right) are of equal sign or when either function(left) or function(right) is "Not a Number".

NullPointerException - when the supplied function is null.