[Maxima-discuss] displaying lisp structure of Maxima expressions.

[Richard F. <fa...@gm...>]

I find that displaying lisp structure in pretty-printed form has much to
recommend it over trying to show trees as graphs with links.

To display a maxima expression in pretty-print form, though with
some abbreviations, consider this program..
...............ppshort.lisp

(defun shorten(r) ;; make maxima general form expression more lisp-like
  (cond ((atom r) r)
(t (cons (caar r)(mapcar #'shorten (cdr r))))))
(defun shortmore(r)
  (cond ((atom r)(shortatom r))
(t (mapcar #'shortmore r))))

(defun shortatom(r)
  (cond
    ((eq r 'mtimes) '*)
    ((eq r 'mplus) '+)
    ((eq r 'mexpt) '^) ;;; etc
    (t r)))

(defun $pp(r)(pprint(shortmore (shorten r))))
;; end of program...............
As an example. consider q:ratsimp((a+b+c+1)^10)$

which is kind of large.  pp(q) shows its structure ... here are the first
few lines
displayed.. Note carefully the indentation, which shows the tree structure..

(+ 1 (* 10 $A) (* 45 (^ $A 2)) (* 120 (^ $A 3)) (* 210 (^ $A 4))
   (* 252 (^ $A 5)) (* 210 (^ $A 6)) (* 120 (^ $A 7)) (* 45 (^ $A 8))
   (* 10 (^ $A 9)) (^ $A 10)
   (*
    (+ 10 (* 90 $A) (* 360 (^ $A 2)) (* 840 (^ $A 3)) (* 1260 (^ $A 4))
       (* 1260 (^ $A 5)) (* 840 (^ $A 6)) (* 360 (^ $A 7)) (* 90 (^ $A 8))
       (* 10 (^ $A 9)))
    $B)
   (*
    (+ 45 (* 360 $A) (* 1260 (^ $A 2)) (* 2520 (^ $A 3)) (* 3150 (^ $A 4))
       (* 2520 (^ $A 5)) (* 1260 (^ $A 6)) (* 360 (^ $A 7)) (* 45 (^ $A 8)))
    (^ $B 2))

....

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