 |
Index for Section 3 |
|
 |
Alphabetical listing for E |
|
erf(3)
NAME
erf, erfc - Error functions
LIBRARY
Math Library (libm.a)
SYNOPSIS
#include <math.h>
double erf (double x);
float erff (float x);
double erfc (double x);
float erfcf (float x);
STANDARDS
Interfaces documented on this reference page conform to industry standards
as follows:
erf(): XPG4
erfc(): XPG4
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
DESCRIPTION
The erf() and erff() functions return the error function of x, where erf(x)
and erff(x) equal (2/sqrt(pi)) times the area under the curve e**(-t**2)
between 0 and x.
The erfc() and erfcf() functions return (1.0 - erf(x)). The erfc()
function can result in an underflow as x gets large.