DOUBLE atan2(DOUBLE y, DOUBLE x) Returns the arc tangent of ‘y’ / ‘x’.
mysql> select atan2(0.1, 0.2); +---------------------+ | atan2(0.1, 0.2) | +---------------------+ | 0.46364760900080609 | +---------------------+ mysql> select atan2(1.0, 1.0); +---------------------+ | atan2(1.0, 1.0) | +---------------------+ | 0.78539816339744828 | +---------------------+
ATAN2