Re: Math markups.

N F Drakos <nikos@cbl.leeds.ac.uk>
X-Delivered: at request of secret on dxcern.cern.ch
Via: uk.ac.leeds.cbl; Wed, 6 Oct 1993 12:36:36 +0100
From: N F Drakos <nikos@cbl.leeds.ac.uk>
Date: Wed, 6 Oct 93 12:36:31 BST
Message-id: <29351.9310061136@cbl.leeds.ac.uk>
To: www-talk <www-talk@nxoc01.cern.ch>
Subject: Re: Math markups.

Emanuel Knill writes:
>
>Hi everyone,
>
>You probably have seen the recent discussion on markups for
>math on comp.infosystems.www. Unfortunately I could not
>so far determine who is actually working on implementing
>mathematical expressions. There are at least five
>mathematicians here who would take immediate advantage
>of such features if they were available. Yes,
>I have seen latex2html, and tried converting some of my
>papers. Though I think it is great to
>have build this tool, the results were not satisfactory for
>what I tried. The most
>obvious problem was symbol alignment.

What is the symbol alignment problem?
If you are referring to equation images not being aligned
correctly within a piece of text that flows around them 
then this can be fixed with the new version of mosaic
(XMosaic 2.0 prerelease 4) and the next release of latex2html
(or the patch to v0.3.1 in
http://cbl.leeds.ac.uk/nikos/tex2html/previous-versions/patch0.3.1-to-0.3.3.txt)

If you want to align several equations then why not use latex 
multiline formulas (eqnarray). Alternatively you can enclose 
whatever equation+text arrangement whose exact presentation style
you want to preserve in an environment that would force the 
generation of an inlined image for it. 

What other problems are there?

>I did notice that html+ will include embedded elements,
>and in fact one of the examples referres to embedded TeX.
>My understanding is that we could have an external program
>which can convert such embedded formulas to an image
>and provide this to the browser for inclusion. Is this correct?
>If so, is anyone working on providing such programs?
>As I see it, the only disadvantage of such an approach
>is that one cannot take advantage of the macro definition
>capabilities of TeX.  Finally, 
>it seems that concepts such as "theorems",
>"lemmas", "examples" etc. should be added to the paragraph
>roles?

Apart from the macro capabilities of TeX, and the 
inclusion of style files there other problems
resulting from the fact that in many cases single equations 
cannot be treated in isolation. For example automatic 
equation numbering, cross references using symbolic 
equation labels, automatic generation
of theorem/subtheorem/axiom/lemma numbers cannot be 
addressed by embedding TeX in HTML unless parts of the 
TeX engine are replicated, or 
as Marc points out, unless TeX becomes more modular
so that it can be used with other packages. 
For the time being these issues can only be addressed if
the equations and the text around them are processed
together and preferably off-line because of potential overheads.

Nikos Drakos 
Computer Based Learning Unit    
University of Leeds

email: nikos@cbl.leeds.ac.uk
WWW  : http://cbl.leeds.ac.uk/nikos/personal.html