[Axiom-developer] Re: [fricas-devel] Re: [sage-devel] Re: [fricas-devel] Re: Project

[Ralf Hemmecke]

Hi William,

On 04/20/2008 05:29 PM, William Stein wrote:
> >  >  On Sun, Apr 20, 2008 at 3:10 AM, Martin Rubey <address@hidden> wrote:
> >  >  > I don't have the guts to send this to a public mailing list.  I probably
> >  >  >  should.  If you want to, you have my permission.
> >  >  >
> >  >  >
> >  >  >  "Alfredo Portes" <address@hidden> writes:
> >  >  >
> >  >  >  > >  Axiom is so huge, so if Sage would be a part of Axiom that just 
> > handles
> >  >  >  > > the web interface, why not?
>
> The part of Sage that deals with the web interface is written
> in pure Python and depends only on Python, Twisted, and
> Pexpect.   At present it is somewhat tightly integrated into
> the Sage distribution.  But this is only *temporary*, which
> we intend to change in the future, most likely this summer.
> Thus if you just want to have an Axiom GUI and or web notebook
> interface, you could just ship or depend on
>
>      Python+Twisted+Pexpect+a small part of Sage.

Oh, that looks interesting. The question is, who is going to implement 
that? Are there any volunteers around?

> I don't understand the Axiom distribution enough to understand
> how big it is, but my impression is that it is *also* huge.

Well, one cannot cover a big part of mathematics ant not being huge.

> Looking
> in the src/src/algebra directory there are many hundreds of
> thousands of lines of code (over 300,000 distinct lines just of
> dot-lsp files).  By the way, how do you guys read
> some of this stuff?

Nobody should have need to read LISP. Mathematicians are used to "higher 
level". I would prefer if under src/algebra there would be only spad 
files with nothing but SPAD (or Aldor) and documentation in them.
One can write relatively compact code in SPAD/Aldor and nothing like 
LISP should distract from that.

> I looked in INTALG.lsp and it is
> pages of code that look like this:
>                                              (PROGN
>                                                (LETT #0# NIL
>                                                 |INTALG;palglogint|)
>                                                (SEQ
>                                                 (LETT |q| NIL
>                                                  |INTALG;palglogint|)
>                                                 (LETT #1#
>                                                  (SPADCALL (QCDR |fc|)
>                                                   |lf| (QREFELT $ 79))
>                                                  |INTALG;palglogint|)
>                                                 G190
>                                                 (COND
>                                                   ((OR (ATOM #1#)
>                                                     (PROGN
>                                                       (LETT |q|
>                                                        (CAR #1#)
>                                                        |INTALG;palglogint|)
>                                                       NIL))
>                                                    (GO G191)))
>                                                 (SEQ
>                                                  (EXIT
>                                                   (LETT #0#
>                                                    (CONS
>                                                     (SPADCALL
>                                                      (SPADCALL
>                                                       (QCAR |q|) 0
>                                                       (QREFELT $ 82))
>                                                      (QREFELT $ 83))
>                                                     #0#)
>                                                    |INTALG;palglogint|)))
>
> This is from INTALG.lsp.  Surely this is some machine-generated
> code that isn't meant to be human readable, so I'm
> measuring the wrong thing!

Of course. And of course, nobody reads that. Or is there someone?

> How does the fricas/axiom source code layout work?
> Is it all written in pamphlets that lisp is generated from?
> Anyway, I would love if somebody who knows what they
> are talking about regarding axiom (not me!) would
> explain what the human-written/readable code
> parts of the axiom distro are and roughly how big each is,
> in some sense.

William, since you are an invited speaker at ISSAC, why not staying a 
little longer and attending the Aldor & Axiom Workshop right after 
ISSAC? There might be some people around that could explain.

> And who are some of the Axiom original
> authors?  Some files have headers like:

> ++ Author: Grabmeier, Gschnitzer, Williamson
> ++ Date Created: 1987
> ++ Date Last Updated: July 1990
>
> I wonder who those guys were...?

I agree, nothing is perfect. But as for this particular case, I know Dr. 
Johannes Grabmeier personally, and since he is working near Linz, he 
might be around at the Aldor & Axiom Workshop.

Ralf