/sys$common/syshlp/helplib.hlb RTL Routines, MTH$, MTH$xATAN  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Given the tangent of an angle, the Arc Tangent in Radians routine
    returns that angle (in radians).

    Format

      MTH$ATAN  tangent

      MTH$DATAN  tangent

      MTH$GATAN  tangent

      Each of the above formats accepts one of the floating-point
      types as input.

  Additional Information (explode) :

• Corresponding JSB Entry Points
• Returns
• Argument