Returns the arc-tangent, in radians, of a number.
ATAN( numeric-expression )
The ATAN and TAN functions are inverse operations.
numeric-expression The tangent of the angle.
This function converts its argument to DOUBLE, performs the computation in double-precision floating point, and returns a DOUBLE as the result.
SQL/2003 Vendor extension.
The following statement returns the arc-tangent value for 0.52.
SELECT ATAN( 0.52 );