Arc Tangent of Y/X

This function returns ATN(y/x) and is specific only to SQL Server. We have included it for compatibility.

From SQL Server documentation:

Returns the angle, in radians, between the positive x-axis and the ray from the origin to the point (y, x), where x and y are the values of the two specified float expressions.

The function may be simulated by using the following formula:

Atn2 = ATN(y / x)

Remarks

This function is not part of the SQL Spec, but is included for SQL Server compatibility.

Example

SELECT ATN2(35.175643,129.44)

RETURNS:  0.265344532064832