Package org.apache.commons.numbers.gamma

Class Erf

java.lang.Object
org.apache.commons.numbers.gamma.Erf
public class Erf
extends java.lang.Object
Error function.

  • Constructor Summary

    Constructors 
    Constructor Description
    Erf()  

  • Method Summary

    Modifier and Type Method 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

  • Constructor Details

    • Erf

      public Erf()

  • Method Details

    • 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:
      java.lang.ArithmeticException - if the algorithm fails to converge.
      See Also:
      RegularizedGamma.P.value(double, double, double, int)