ERF(3)                      BSD Programmer's Manual                     ERF(3)

NAME
     erf, erfc - error function operators

SYNOPSIS
     #include <math.h>

     double
     erf(double x)

     double
     erfc(double x)

DESCRIPTION
     These functions calculate the error function of x.

     The erf() calculates the error function of x; where

           erf(x) = 2/sqrt(pi)*integral from 0 to x of exp(-t*t) dt.

     The erfc() function calculates the complementary error function of x;
     that is erfc() subtracts the result of the error function erf(x) from
     1.0.  This is useful, since for large x places disappear.

SEE ALSO
     math(3)

HISTORY
     The erf() and erfc() functions appeared in 4.3BSD.

4.3 Berkeley Distribution       March 26, 1993                               1