java.lang.Object
org.apache.commons.numbers.gamma.Erf

public final class Erf extends Object
Error function.

\[ \operatorname{erf}(z) = \frac{2}{\sqrt\pi}\int_0^z e^{-t^2}\,dt \]

  • Constructor Details

    • Erf

      private Erf()
      Private constructor.
  • Method Details

    • value

      public static double value(double x)
      Returns the error function.

      The returned value is always between -1 and 1 (inclusive). The appropriate extreme is returned when erf(x) is indistinguishable from either -1 or 1 at double precision.

      Special cases:

      • If the argument is 0, then the result is 0.
      • If the argument is > 6, then the result is 1.
      • If the argument is < 6, then the result is -1.
      • If the argument is nan, then the result is nan.
      Parameters:
      x - the value.
      Returns:
      the error function.