Name

erf, erff, erfl, erfc, erfcf, erfcl — error function and complementary error function

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);
[Note] Note
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
All functions shown above: _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE || _ISOC99_SOURCE;
or cc -std=c99
[Note] Note

Link with −lm.

DESCRIPTION

The erf() function returns the error function of x; defined as

erf(x) = 2/sqrt(pi)* integral from 0 to x of exp(−t*t) dt

The erfc() function returns the complementary error function of x, that is 1.0 − erf(x).

CONFORMING TO

SVr4, 4.3BSD, C99. The float and long double variants are requirements of C99.

SEE ALSO

cerf(3), exp(3)

COLOPHON

This page is part of release 2.79 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.


  Copyright 1993 David Metcalfe (davidprism.demon.co.uk)

Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided that the
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permission notice identical to this one.

Since the Linux kernel and libraries are constantly changing, this
manual page may be incorrect or out-of-date.  The author(s) assume no
responsibility for errors or omissions, or for damages resulting from
the use of the information contained herein.  The author(s) may not
have taken the same level of care in the production of this manual,
which is licensed free of charge, as they might when working
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Formatted or processed versions of this manual, if unaccompanied by
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References consulted:
    Linux libc source code
    Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
    386BSD man pages
Modified 1993-07-24 by Rik Faith (faithcs.unc.edu)
Modified 2002-07-27 by Walter Harms
(walter.harmsinformatik.uni-oldenburg.de)