ArcTan                   Returns the Arctangent of a Value

 ArcTan(Tangent : Real) : Real;
 ArcTan(Tangent : Integer) : Real;

    Returns the arc-tangent of Tangent; i.e., if Tan(X) = Tangent,
    ArcTan(Tangent) = X. The value returned is in radians.

         Tangent    An integer or real value (constant, variable, function
                    call, or expression).

         Limits:    none

  -------------------------------- Example ---------------------------------

           X := ArcTan(1) * (180/Pi);       { X = 45.0 (degrees) }