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),