ERF(3) BSD Library Functions Manual ERF(3)
NAME
erf, erff, erfc, erfcf -- error function operators
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
erf(double x);
float
erff(float x);
double
erfc(double x);
float
erfcf(float 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.
BSD
April 20, 1991 BSD
