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ERF 3M "Jul 12, 2006" "SunOS 5.11" "Mathematical Library Functions"
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(\c \c ) * 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)