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RE: Any computer/math experts out there?


From: Jukka Korpela
Date: Sep 13, 2002 5:03AM

Hencmann, Maureen wrote:

> We are struggling with this question in both math and computer
> science courses.

That means quite some challenges. One of key problems is that mathematical
notations are primarily written (not spoken) language and often involve
two-dimensionality. Besides, the HTML markup system is very limited as
regards to mathematical expressions, and many of the tricks used to
circumvent the limitations and to get tolerable visual presentation, cf. to
my "tools & tricks collection" at
will imply problems in non-visual presentation. Moreover, when the document
is presented as visible or tangible characters, there can be serious
limitations in the character repertoire that can be used in particular

> Please see the attached information and advise how we can
> make this content accessible, which has both color highlighting and
> hexidecimal/binary/ addition problems with strike throughs?

It would be better to post URLs of demo documents. Now the first document
contains essentially an image reference, but the image is absent and there
is no ALT text. The second one has some use of colors and bolding but no
strike throughs, as far as can tell.

In auditive presentation, and in several forms of visual presentation,
features like italics vs. upright style, bolding, and strike-through are
lost, and so is color highlighting (in part or completely). So none of them
should really be relied on, even if the WAI guidelines explicitly mentions
only "don't trust on color alone". But in mathematics, physics, etc., such
features may be conventional and essential meaning. I don't think there is
any general solution; just partial solutions for different specific cases.

Your second example contains some minor problems as regards to
- empty paragraphs, <p></p>, which may result in unnecessary pauses
- the use of letter x as multiplication symbol; this might result in "2 x 2"
being pronounced as "two ex two"; better use &times; (or