ATAN2(3) Linux Programmer's Manual ATAN2(3)

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, asin, atan, cos, sin, tan,

 June 8, 1993 1

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