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atan2, atan2f
[arc tangent of y/x]

SYNOPSIS

    #include <math.h>
    double atan2(double y,double x);
    float atan2f(float y,float x);

DESCRIPTION

atan2 computes the inverse tangent (arc tangent) of y/x. atan2 produces the correct result even for angles near /2 or /2, that is, when x is near 0).

atan2f is identical to atan2, save that it takes and returns float.

RETURNS

atan2 and atan2f return a value in radians, in the range of
to . If both x and y are 0.0, atan2 causes a DOMAIN error. You can modify error handling for these functions using matherr.

COMPLIANCE

atan2 is ANSI C. atan2f is an extension.