Table of Contents

Name

atan2, atan2f, atan2l - arc tangent function of two variables

Synopsis


#include <math.h>
double atan2(double y, double x);
float atan2f(float y, float x);
long double atan2l(long double y, long 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. The float and long double variants are C99 requirements.

See Also

acos(3) , asin(3) , atan(3) , cos(3) , sin(3) , tan(3)


Table of Contents