erf(3) BSD Library Functions Manual erf(3)
NAME
erf, erfc -- error function operators
SYNOPSIS
#include <math.h>
double
erf(double x);
long double
erfl(long double x);
float
erff(float x);
double
erfc(double x);
long double
erfcl(long double x);
float
erfcf(float x);
DESCRIPTION
These functions calculate the error function of x.
The erf() function 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() computes the difference of the error function erf(x) from
1.0. This is useful, since for large x use of erfc() avoids loss of pre-
cision due to cancellation.
SPECIAL VALUES
erf(+-0) returns +-0.
erf(+-infinity) returns +-1.
erfc(-infinity) returns 2.
erfc(+infinity) returns +0.
SEE ALSO
math(3)
STANDARDS
The erf() and erfc() functions conform to ISO/IEC 9899:2011.
4.3 Berkeley Distribution December 11, 2006 4.3 Berkeley Distribution
Mac OS X 10.9.1 - Generated Tue Jan 7 19:09:38 CST 2014