atan2 - chung-leong/qb GitHub Wiki
atan2 - Arc tangent of two variables
float atan2 ( float $x, $y )
This 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.
The function returns the result in radians, which is between -PI and PI (inclusive).
Parameters:
x - The denominator. It can be a scalar or an array.
y - The nominator. It can be a scalar or an array.
Return Value:
The arc tangent of y / x in radians. If x or y is an array, the return value will also be an array, the size of which matches the larger of x and y.
Version
1.0 and above.