Correcting priority issues in mactex.lisp

Robert Dodier wrote:
> On Tue, May 26, 2009 at 10:19 AM, Richard Fateman
> <fateman at cs.berkeley.edu> wrote:
>
>   
>> If we start putting in extra parentheses each time someone claims to be
>> confused, it may not end here.
>>     
>
> Sure. That's why it's a good idea to consider each change case-by-case,
> as we are doing now.
>
>   
I think that there are principles for display that at play here.  One of 
them is that using mactex for the sole output form ( as in imaxima ?) is 
probably not an adequate solution for interactive display.
I think this is an imaxima problem, not a mactex problem, as illustrated 
by the Mathematica variations in display.
>> Time for a flag?  Perhaps something like add_extra_parens:   all    or some
>>    or none {situation now}.
>>     
>
> Another flag? Ugh.
>
>   
The alternatives seem to be
(a) reach a consensus.  Sometimes this is possible because only one 
person, the one making the change, is the only one with an opinion, and 
everyone else goes along with it.
(b) fork the project.
(c) add a flag.
(d) reject the change.
(e) impose the change without a consensus. [e.g. just insert a "bug fix" 
even if it is wrong]
(f) do what Mathematica does and have TraditionalForm, InputForm, 
FullForm, TeXForm  functions.  (there may be more..)
(g) fork mactex for imaxima.

anything else?
 All things considered, (c) and (g) seem most plausible.
Imposing full disambiguity on every use of mactex is going to result in 
lots of parentheses, most of which interfere with the most-compact 
conventional display.  By the way, looking at old integral tables, there 
are several conventions on display that have faded from common 
practice,  but as I recall, in the table by Bierens de Haan there are 
two multiplication operators (at least). One is adjacency as in x y  and 
another is \centerdot.   They have different precedences.  Do we want 
that, too?  We could also campaign for different parentheses, e.g. {} [] 
to be used in display. I think that is potentially very very helpful.

I suggest that imaxima do as many of these things as the authors of 
imaxima wish.  So perhaps forking mactex is appropriate.

My own experience in taking the output from Macsyma/Maxima 's  mactex 
and putting it in to papers is that it almost always needs some editing 
by hand to get the desired "natural" display.   For example $b+a$ might 
be better as $a+b$. Adding parentheses is not something I recall ever doing.


RJF


>> not what I see.    I see  (  sum(a[n]+b[n],n,1,k)    ) + ....
>> not                               sum(   ( a[n]+b[n]  )  , n,1,k) + ... if
>> that is clear :)
>>     
>
> Are you using wxMaxima? I mean the 2-d display in command line Maxima.
> What does build_info say?
>
>   
Maxima version: 5.17.0
Maxima build date: 19:8 12/4/2008
host type: i686-pc-mingw32
lisp-implementation-type: GNU Common Lisp (GCL)
lisp-implementation-version: GCL 2.6.8

in wxmaxima, try
'sum(b[n]+a[n],n,1,k)+a[n]$

RJF