org.apache.commons.numbers.gamma

Class Erf

java.lang.Object

org.apache.commons.numbers.gamma.Erf

public final class Erf
extends Object

Error function.

Method Summary

Modifier and Type	Method and Description
static double	value(double x) This implementation computes erf(x) using the regularized gamma function, following Erf, equation (3)

Methods inherited from class java.lang.Object

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

Method Detail

value

public static double value(double x)

This implementation computes erf(x) using the regularized gamma function, following Erf, equation (3)

The returned value is always between -1 and 1 (inclusive). If abs(x) > 40, then Erf.value(x) is indistinguishable from either 1 or -1 at double precision, so the appropriate extreme value is returned.

Parameters:

x - the value.

Returns:

the error function.

Throws:

ArithmeticException - if the algorithm fails to converge.

See Also:

RegularizedGamma.P.value(double, double, double, int)