NAME

erf, erff, erfc, erfcf - error function operators

LIBRARY

Math Library (libm, -lm)

SYNOPSIS



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.