displa for sub and superscripted functions



I thought of one way to display the superscript of the Jacobi polynomials; 
as in

      (a,b)
    J       (x)
     n

I tell Maxima that the exponent is a function whose name is an empty 
string.  When
that gets displayed, only the arguments surrounded by parens are shown.  I 
used
something like 

 (setq form `((mexpt) ((,fn simp array) ,@lo) (("") ,@hi))))


where fn = "J", hi = (a b), and lo = (n) to get jacobi_p(n,a,b,x) to 
display correctly.

Barton