Reference

erf(3)

error function operators

NAME

erf, erff, erfl, erfc, erfcf, erfcl – error function operators

LIBRARY

Math Library (libm, -lm)

SYNOPSIS

#include <math.h>

double

erf(double x);

float

erff(float x);

long double

erfl(long double x);

double

erfc(double x);

float

erfcf(float x);

long double

erfcl(long double x);

DESCRIPTION

These functions calculate the error function of x.

The erf(), erff(), and erfl() functions calculate the error function of x; where

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

The erfc(), erfcf(), and erfcl() functions calculate the complementary error function of x; that is erfc() subtracts the result of the error function erf(x) from 1.0.

SEE ALSO

math(3)

STANDARDS

The erf(), erff(), erfl(), erfc(), erfcf() and erfcl() functions conform to ISO/IEC 9899:1999 (“ISO C99”).

HISTORY

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

History