ERF Function

Evaluates the real error function erf(x). Using a keyword, the inverse error function erf ^–1(x) can be evaluated.

Usage

result = ERF(x)

Input Parameters

x—Expression for which the error function is to be evaluated.

Returned Value

result—The value of the error function erf(x).

Input Keywords

Double—If present and nonzero, double precision is used.

Inverse—Evaluates the real inverse error function erf^–1(x). The inverse error function is defined only for –1 < x < 1.

Discussion

The error function erf(x) is defined below:

 

All values of x are legal. The inverse error function y = erf ^–1(x) is such that x = erf (y).