ERF(3M) Mathematical Library Functions ERF(3M)

NAME

erf, erff, erfl - error function

SYNOPSIS

c99 [ flag... ] file... -lm [ library... ]
#include <math.h>

double erf(double x);


float erff(float x);


long double erfl(long double x);

DESCRIPTION

These functions compute the error function of their argument x,
defined as:

2/sqrt(pi)*intregral from 0 to x of exp(-t*t) dt

RETURN VALUES

Upon successful completion, these functions return the value of the
error function.


If x is NaN, a NaN is returned.


If x is +-0, +-0 is returned.


If x is +-Inf, +-1 is returned.


If x is subnormal, 2/sqrt(pi) * 2 is returned.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+----------------------------+-----------------------------+
|Interface Stability | Standard |
+----------------------------+-----------------------------+
|MT-Level | MT-Safe |
+----------------------------+-----------------------------+

SEE ALSO

math.h(3HEAD), erfc(3M), feclearexcept(3M), fetestexcept(3M),
isnan(3M), attributes(7), standards(7)

SunOS 5.11 July 12, 2006 ERF(3M)