ERF(3) NEWLIB ERF(3)NAME
1.14 `erf', `erff', `erfc', `erfcf'--error function
SYNOPSIS
#include <math.h>
double erf(double X);
float erff(float X);
double erfc(double X);
float erfcf(float X);
DESCRIPTION
`erf' calculates an approximation to the "error function", which esti‐
mates the probability that an observation will fall within X standard
deviations of the mean (assuming a normal distribution).
`erfc' calculates the complementary probability; that is, `erfc(X)'
is `1 - erf(X)'. `erfc' is computed directly, so that you can use it
to avoid the loss of precision that would result from subtracting large
probabilities (on large X) from 1.
`erff' and `erfcf' differ from `erf' and `erfc' only in the argument
and result types.
RETURNS
For positive arguments, `erf' and all its variants return a probabil‐
ity--a number between 0 and 1.
PORTABILITY
None of the variants of `erf' are ANSI C.
SEE ALSOerf is part of the library. The full documentation for is maintained
as a Texinfo manual. If info and are properly installed at your site,
the command
info
will give you access to the complete manual.
NEWLIB April 2010 ERF(3)
