NAME
        IEEESPAtan -- compute the arc tangent of number

   SYNOPSIS
          x   = IEEESPAtan(  y  );
        d0                 d0

        single  x,y;

   FUNCTION
        Compute arctangent of y in IEEE single precision

   INPUTS
        y - IEEE single precision floating point value

   RESULT
        x - IEEE single precision floating point value

   BUGS

   SEE ALSO