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RE: MathML-Presentation specs criticized.

From: Jimmy Cerra <jimbofc@yahoo.com>
Date: Wed, 17 Apr 2002 00:15:22 -0400
To: "'Paul Libbrecht'" <paul@activemath.org>, "'David Carlisle'" <davidc@nag.co.uk>
Cc: <www-math@w3.org>
Message-ID: <000101c1e5c6$81af9e20$0100a8c0@locutus>
> Mmmmh, how would you read the following arriving by some chance on a
> web-page??
>     -      -
>    |   17   |
>    |        |
>    |   34   |
>     -      -
> (square bracket surrounding something like an invisible fraction of 17 and 34)
>
> I know at least that it exists (in combinatorics) and that I do not remember
> what it is anymore.

If you asked me two days ago, I would have said a matrix.  Now, I think it could
be a matrix, a binomial coefficient, an array or an ordered pair.  No, let say
that it is a matrix (table of data) of something such as a generic matrix, a
spatial matrix, an ordered pair, a binominal coefficient and so on.

I understand your point* that presentation alone cannot represent the full
meaning of a mathematical expression.  However, my point was that the content
markup cannot fully express the meaning either.  Both semantics and presentation
are needed to convey the full meaning of an expression (semantic markup for
explicit meaning and presentation markup for emphasis and "thought-process"
meaning).  I feel there should be a better way to combine presentation and
semantic markup  I still don't know why a generic scheme for either combining
generic presentation** markup and semantics or extending presentation markup so
authors can specify the exact meaning of their presentation markup isn't
necessary or in the specs(did I use a double negative!?!?).

I'm sorry if the point I'm apparently missing hasn't sunk into my thick skull
yet. :-)



> I do not think multiple output-targets (a paper, a screen-view, braille,
> audio...) has any chance with MathML-P as source.  What you really want as
> universal mathematics language is content markup and that a stylesheet makes
> the conversion to the appropriate viewer language.

Interesting..... I'm getting ideas.... (oh no!)  See "MathML- Content markup,
Modules, eXtensibility, and more thoughts."***



> Encoding mathematics with content-markup (we also often use the name
> "semantic") and presenting through a stylesheet allows mathematicians to
> define new symbols that only their documents and stylesheets should know. And
> they do!

So noted! :)
---
Jimmy Cerra

* In fact, I'm starting to think a little differently than yesterday (then
again, I've been forming ideas daily and my opinions have been in flux for the
last several weeks).

** by "generic presentation" markup, I mean media and cultural independent
layout markup.  This layout markup specifies how elements relate to each other.
To use an analogy of a sentence (if MathML related to English and not math): a
layout markup would specify the subject and predicate (and possibly importance);
a presentation markup would specify the typography; a semantics markup would
indicate token verbs, nouns, adjectives, and individual words like "for" and
"and" and "he/she/it".

*** URL: http://lists.w3.org/Archives/Public/www-math/2002Apr/0070.html





-----Original Message-----
From: Paul Libbrecht [mailto:paul@activemath.org]
Sent: Tuesday, April 16, 2002 6:29 PM
To: jimbofc@yahoo.com; David Carlisle
Cc: www-math@w3.org
Subject: Re: MathML-Presentation specs criticized.


On Mardi, avril 16, 2002, at 03:46 , Jimmy Cerra wrote:
> I'm not an expert (although I pretend to be :) but I think that if the
> meaning of the layout changes, then the entire equation's meaning
> changes from culture to culture.  This corrupts the data stored in MMLP.

Mmmmh, how would you read the following arriving by some chance on a
web-page??
    -      -
   |   17   |
   |        |
   |   34   |
    -      -
(square bracket surrounding something like an invisible fraction of 17
and 34)

I know at least that it exists (in combinatorics) and that I do not
remember what it is anymore.

> To be a universal mathematics data format, there must be a single way to
> encode the meaning of the equation while also allowing for multiple
> layouts.  Paradoxically, the layout is part of the content, so the
> presentation language should allow multiple layouts of the same code.

I do not think multiple output-targets (a paper, a screen-view, braille,
audio...) has any chance with MathML-P as source.
What you really want as universal mathematics language is content markup
and that a stylesheet makes the conversion to the appropriate viewer
language.

In the square-bracketed fraction up-there, a good stylesheet would not
only present the view (in MathML-P, in TeX, or in PDF) but also provide
something like a roll-over effect to remember you (and me) what is the
name of the symbol and possibly allow you to reach a definition.

Encoding mathematics with content-markup (we also often use the name
"semantic") and presenting through a stylesheet allows mathematicians to
define new symbols that only their documents and stylesheets should
know. And they do!

Paul

  =================================================================
  = Paul Libbrecht       Java developer    The ActiveMath project =
  = http://www.activemath.org/~paul           paul@activemath.org =
  =================================================================
Received on Wednesday, 17 April 2002 00:15:19 GMT

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