ATAN2(3) Linux Programmers Manual ATAN2(3)
NAME
atan2, atan2f, atan2l  arc tangent function of two variables
SYNOPSIS
#include
double atan2(double y, double x);
float atan2f(float y, float x);
long double atan2l(long double y, long double x);
Link with lm.
DESCRIPTION
The atan2() function calculates the arc tangent of the two variables x
and y. It is similar to calculating the arc tangent of y / x, except
that the signs of both arguments are used to determine the quadrant of
the result.
RETURN VALUE
The atan2() function returns the result in radians, which is between
PI and PI (inclusive).
CONFORMING TO
SVr4, POSIX.12001, 4.3BSD, C89. The float and long double variants
are C99 requirements.
SEE ALSO
acos(3), asin(3), atan(3), cos(3), sin(3), tan(3)
COLOPHON
This page is part of release 3.05 of the Linux manpages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/manpages/.
20020727 ATAN2(3)
