+++ /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-.\" manual page may be incorrect or out-of-date.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 ATAN2 3 2010-09-20 "" "Linux Programmer's Manual"
-.SH NAME
-atan2, atan2f, atan2l \- arc tangent function of two variables
-.SH SYNOPSIS
-.nf
-.B #include <math.h>
-
-.BI "double atan2(double " y ", double " x );
-.BI "float atan2f(float " y ", float " x );
-.BI "long double atan2l(long double " y ", 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 atan2f (),
-.BR atan2l ():
-.RS
-_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 atan2 ()
-function calculates the principal value of the arc tangent of
-.IR y/x ,
-using the signs of the two arguments to determine
-the quadrant of the result.
-.SH RETURN VALUE
-On success, these functions return the principal value of the arc tangent of
-.IR y/x
-in radians; the return value is in the range [\-pi,\ pi].
-
-If
-.I y
-is +0 (\-0) and
-.I x
-is less than 0, +pi (\-pi) is returned.
-
-If
-.I y
-is +0 (\-0) and
-.I x
-is greater than 0, +0 (\-0) is returned.
-
-If
-.I y
-is less than 0 and
-.I x
-is +0 or \-0, \-pi/2 is returned.
-
-If
-.I y
-is greater than 0 and
-.I x
-is +0 or \-0, pi/2 is returned.
-
-.\" POSIX.1 says:
-.\" If
-.\" .I x
-.\" is 0, a pole error shall not occur.
-.\"
-If either
-.I x
-or
-.I y
-is NaN, a NaN is returned.
-
-.\" POSIX.1 says:
-.\" If the result underflows, a range error may occur and
-.\" .I y/x
-.\" should be returned.
-.\"
-If
-.I y
-is +0 (\-0) and
-.I x
-is \-0, +pi (\-pi) is returned.
-
-If
-.I y
-is +0 (\-0) and
-.I x
-is +0, +0 (\-0) is returned.
-
-If
-.I y
-is a finite value greater (less) than 0, and
-.I x
-is negative infinity, +pi (\-pi) is returned.
-
-If
-.I y
-is a finite value greater (less) than 0, and
-.I x
-is positive infinity, +0 (\-0) is returned.
-
-If
-.I y
-is positive infinity (negative infinity), and
-.I x
-is finite,
-pi/2 (\-pi/2) is returned.
-
-If
-.I y
-is positive infinity (negative infinity) and
-.I x
-is negative infinity, +3*pi/4 (\-3*pi/4) is returned.
-
-If
-.I y
-is positive infinity (negative infinity) and
-.I x
-is positive infinity, +pi/4 (\-pi/4) is returned.
-.\"
-.\" POSIX.1 says:
-.\" If both arguments are 0, a domain error shall not occur.
-.SH ERRORS
-No errors occur.
-.\" POSIX.1 documents an optional underflow error
-.\" glibc 2.8 does not do this.
-.SH CONFORMING TO
-C99, POSIX.1-2001.
-The variant returning
-.I double
-also conforms to
-SVr4, 4.3BSD, C89.
-.SH SEE ALSO
-.BR acos (3),
-.BR asin (3),
-.BR atan (3),
-.BR carg (3),
-.BR cos (3),
-.BR sin (3),
-.BR tan (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/.
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