+++ /dev/null
-.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
-.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
-.\" <mtk.manpages@gmail.com>
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" 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
-.\" entire resulting derived work is distributed under the terms of a
-.\" 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-.\" manual page may be incorrect or out-of-date.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
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" 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 (faith@cs.unc.edu)
-.\" Modified 2002-07-27 by Walter Harms
-.\" (walter.harms@informatik.uni-oldenburg.de)
-.\"
-.TH ERF 3 2013-10-29 "GNU" "Linux Programmer's Manual"
-.SH NAME
-erf, erff, erfl, \- error function
-.SH SYNOPSIS
-.nf
-.B #include <math.h>
-
-.BI "double erf(double " x );
-.BI "float erff(float " x );
-.BI "long double erfl(long double " x );
-
-.fi
-Link with \fI\-lm\fP.
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.ad l
-.BR erf ():
-.RS 4
-_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE || _ISOC99_SOURCE ||
-_POSIX_C_SOURCE\ >=\ 200112L;
-.br
-or
-.I cc\ -std=c99
-.RE
-.br
-.BR erff (),
-.BR erfl ():
-.RS 4
-_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE ||
-_POSIX_C_SOURCE\ >=\ 200112L;
-.br
-or
-.I cc\ -std=c99
-.RE
-.ad b
-.SH DESCRIPTION
-The
-.BR erf ()
-function returns the error function of
-.IR x ,
-defined
-as
-.TP
- erf(x) = 2/sqrt(pi)* integral from 0 to x of exp(\-t*t) dt
-.SH RETURN VALUE
-On success, these functions return the error function of
-.IR x ,
-a value in the range [\-1,\ 1].
-
-If
-.I x
-is a NaN, a NaN is returned.
-
-If
-.I x
-is +0 (\-0), +0 (\-0) is returned.
-
-If
-.I x
-is positive infinity (negative infinity),
-+1 (\-1) is returned.
-
-If
-.I x
-is subnormal,
-a range error occurs,
-and the return value is 2*x/sqrt(pi).
-.SH ERRORS
-See
-.BR math_error (7)
-for information on how to determine whether an error has occurred
-when calling these functions.
-.PP
-The following errors can occur:
-.TP
-Range error: result underflow (\fIx\fP is subnormal)
-.\" .I errno
-.\" is set to
-.\" .BR ERANGE .
-An underflow floating-point exception
-.RB ( FE_UNDERFLOW )
-is raised.
-.PP
-These functions do not set
-.IR errno .
-.\" FIXME . Is it intentional that these functions do not set errno?
-.\" Bug raised: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6785
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR erf (),
-.BR erff (),
-and
-.BR erfl ()
-functions are thread-safe.
-.SH CONFORMING TO
-C99, POSIX.1-2001.
-The variant returning
-.I double
-also conforms to
-SVr4, 4.3BSD.
-.SH SEE ALSO
-.BR cerf (3),
-.BR erfc (3),
-.BR exp (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
OSDN Git Service
