An (eev-based) alternative to emaxima.sty

Long story short, in an image...
In this page I explain how I convert Maxima logs to LaTeX -
and how I generate things that look like this (click to go to the PDF):

My main page on Maxima is here.

1. Introduction: emaxima.sty

Maxima comes with something called "EMaxima", whose main files - for me - are these ones:

(find-maximagitfile "doc/emaxima/")
(find-maximagitfile "doc/emaxima/EMaximaIntro.tex")
(find-maximagitfile "interfaces/emacs/emaxima/")
(find-maximagitfile "interfaces/emacs/emaxima/emaxima.lisp")
(find-maximagitfile "interfaces/emacs/emaxima/emaxima.sty")
(find-maximagitfile "interfaces/emacs/emaxima/maxima-font-lock.el")
(find-maximagitfile "interfaces/emacs/emaxima/maxima.el")

I was mainly interested in one feature of emaxima.sty - the one that is explained in page 10 of its manual, that typesets LaTeX blocks like this one,

\begin{maximasession}
diff(sin(x),x);
integrate(cos(x),x);
\maximaoutput*
\i5. diff(sin(x),x); \\
\o5. \cos x \\
\i6. integrate(cos(x),x); \\
\o6. \sin x \\
\end{maximasession}

The definition of the environment `maximasession' in emaxima.sty uses catcodes heavily, and so I couldn't put "\begin{maximasession} ... \end{maximasession}" blocks inside "\vbox"es or "\scalebox"es - it would by better to reimplement `maximasession' in another way.

The package `emaxima.sty' is a bit hard to use.

What I am going to explain in this page is an alternative to `emaxima.sty' that is much harder to use - and almost impossible to use if you are not me - but that has some ideas that I think that are worth documenting.

2. `emaxima.lisp'

If we run this

* (eepitch-maxima)
* (eepitch-kill)
* (eepitch-maxima)
load("/usr/share/emacs/site-lisp/maxima/emaxima.lisp")$
:lisp (setf (get '$display2d 'assign) nil)
display2d:'emaxima$
linenum:0;
diff(sin(x),x);
integrate(cos(x),x);

the last part of the log is:

(%i1) diff(sin(x),x);
(%o1) \cos x
(%i2) integrate(cos(x),x);
(%o2) \sin x
(%i3) 

that is similar to the syntax that `maximasession' understands.
Here is the reason for the `setf':

(find-es "maxima" "emaxima-bug-2024jul20")
(find-maximamsg "58797458 202407 21" "Edrx: display2d:'emaxima; fails in a recent Maxima")
(find-maximamsg "58797475 202407 21" "RDodier: :lisp (setf (get '$display2d 'assign) nil)")

3. Maxima2.lua

Dednat6 is a LaTeX package that I wrote, and that I use to typeset many kinds of diagrams. It very unpopular: I only know one person who uses, or who has used it, besides me - a friend of mine called Fernando Lucatelli - but Dednat6 is very easy to extend, and sometimes I write new extensions for it as quick hacks.

One of these extensions is Maxima2.lua. If I put this in a LaTeX file at any point after the part that loads Dednat6,

%L dofile "Maxima2.lua"
\pu

%M (%i1) diff(sin(x),x);
%M (%o1) \cos x
%M (%i2) integrate(cos(x),x);
%M (%o2) \sin x
%M (%i3)
%L maximahead:sa("sin-cos", "")
\pu

\def\hboxthreewidth {14cm}
\ga{sin-cos}

the "dofile" loads Maxima2.lua, that defines "%M" as a new "head"; the code for that is here. Then when Dednat6 processes the "%M"-block it simply puts the lines after the "%M"s into the global variable maxima_lines as a multi-line string, and when Dednat6 processes this line

%L maximahead:sa("sin-cos", "")

it "output"s this LaTeX code:

\sa{sin-cos}{%
  \vbox{%
    \maximablue{(\%i1)\ diff(sin(x),x);}%
    \maximared{(\%o1)\ }{}%
    \maximared{}{\cos x}%
    \maximared{}{}%
    \maximablue{(\%i2)\ integrate(cos(x),x);}%
    \maximared{(\%o2)\ }{}%
    \maximared{}{\sin x}%
    \maximared{}{}%
    \maximablue{(\%i3)}%
  }%
}

The definitions for "\sa", "\ga", "\maximablue", and "\maximared" are here:

(find-LATEX "edrx21.sty" "sa-and-ga")
(find-LATEX "edrx21.sty" "maximablue-red")

The "%M"-block is easy to tweak by hand. The "output" sends some (ugly!) TeX code both to the TeX part of lualatex and to stdout - it appears in the log, but I usually don't look at it.

Note that the " "s and the "%"s in the "(%i)" lines of the "%M"-block were converted to "\%"s and "\ "s. This was done by Co1.lua, as a trick to quote certain characters without needing to change catcodes.

The "\sa{sin-cos}" is a kind of "\def". I can expand its definition using "\ga{sin-cos}" - and I can do that inside the macros that I use for scaled multicolumn output.

4. Maxima2.lua: a demo

You can see a non-trivial example in this PDF. Note that it has a page that has two matrices with diagrams in its entries, that looks like this:

See my page on Qdraw and MyQdraw for some explanations - but they are very incomplete at this moment. Links:

(find-LATEX "2024-2-C3-maxima-conics.tex" "M-blocks")
(find-es "qdraw" "some-conics")

To download the source of that PDF and compile it on your machine, run this:

* (eepitch-shell)
* (eepitch-kill)
* (eepitch-shell)
rm -rfv  /tmp/edrx-latex/
rm -rfv  /tmp/2024-2-C3-maxima-conics.zip
wget -P  /tmp/ http://anggtwu.net/LATEX/2024-2-C3-maxima-conics.zip
mkdir    /tmp/edrx-latex/
unzip -d /tmp/edrx-latex/ /tmp/2024-2-C3-maxima-conics.zip
cd       /tmp/edrx-latex/
lualatex 2024-2-C3-maxima-conics.tex
# (find-fline    "/tmp/edrx-latex/")
# (find-pdf-page "/tmp/edrx-latex/2024-2-C3-maxima-conics.pdf")

5. `find-Maxima2-links'

To generate an "%M"-block from a Maxima program I use `M-x find-Maxima2-links' - where find-Maxima2-links is a very messy 5-minute hack.