ATAN2
Section: Linux Programmer's Manual (3)
Updated: June 8, 1993
NAME
atan2 - arc tangent function of two variables
SYNOPSIS
#include <math.h>
double atan2(double y, double x);
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
SVID 3, POSIX, BSD 4.3, ISO 9899
SEE ALSO
acos(3), asin(3), atan(3), cos(3), sin(3), tan(3)