[Blindmath] Format for matrices

[Richard Baldwin]

Andrew,

The link that you sent was very helpful. The MathML rendered properly in
Firefox and Chrome, but did not render properly in IE9. IE9 rendered the
MathML as "[Math Processing Error]"

When I listened to your example A, which is a 3x4 rectangular matrix
containing 12 numbers, what I heard was a voice calling out the following
15 individual digits in column order:

1 4 7 1 0 2 5 8 1 1 3 6 9 1 2

The ten was turned into the words "one zero" with no indication that it
really represented the value ten and the eleven was turned into the words
"one one" with no indication that it really represented eleven. I don't
know how a blind person could possibly make sense of that. If there is a
tool that is readily available to blind students that can handle that
matrix in an accessible way, I would like to hear about it, and for that
reason, I am going to repost this message on the blindmath mailing list.

By the way, the link to the sample is
http://mathsnotes.math.ntnu.no/mathsnotes/show/homework+2011+8 just in case
the earlier material gets chopped by my email client.

As to your last paragraph about "letting someone else do it," I agree and
would prefer to use a standard such as MathML provided that it results in
an accessible document. However, there isn't much point in doing the work
if it can't be read by a large portion of the target audience.

Thanks again
Dick Baldwin

On Thu, Nov 10, 2011 at 4:50 AM, Andrew Stacey
<andrew.stacey at math.ntnu.no>wrote:

> On Thu, Nov 10, 2011 at 04:34:16AM -0600, Richard Baldwin wrote:
> >    Someone earlier posted the xhtml code for an identity matrix in this
> >    thread. There were a few errors that needed correcting (probably due
> to
> >    email corruption) but once I got them corrected, I was able to view
> the
> >    page in IE8, IE9, and Firefox. All I got was a string of numbers that
> >    could have represented anything.
>
> Matrices in MathML are very definitely matrices, so that suggests that
> either
> through the corruption or the fixes then something went more wrong than it
> should have done.
>
> >    I could use some help with this, so if you have something, please send
> >    it.
>
> Happy to.
>
> >    What am I looking for? I am looking for a representation of matrix
> >    equations that would be recognizable as such by both blind and sighted
> >    students. To sighted students, a matrix is not normally just a string
> >    of numbers. Rather, it is a grid of numbers, comprising several lines
> >    of print, typically with long vertical lines on both sides of the
> grid.
> >    I recognize that such a format is impractical for use with screen
> >    readers and Braille displays that allow you to see only one line of
> >    print at a time. Therefore, I am looking for a print format that is
> >    compatible with single-line reading devices such as screen readers and
> >    Braille displays that has some history of use within the blind
> >    community.
> >
> >    As I mentioned earlier, one earlier respondent suggested typing all
> the
> >    rows of a square matrix on a single line with the expressions from
> each
> >    row separated from the expressions for the other rows using vertical
> >    bars. Is that an accepted format within the blind community, or is
> >    there some other format that is more common? I can think up lots of
> >    different formats, but I would like to use a format that the blind
> >    community already recognizes as representing a matrix equation.
>
> I can certainly help in some ways, but not in others.  I'm a sighted
> mathematician with no experience of teaching visually impaired students so
> I have no idea how to best represent a matrix for them.
>
> However, I do have considerable experience with generating mathematics, and
> I am keen to find a way to make my material fully accessible, which is why
> I subscribe to this list and (often silently) cheer on your project.
>
> If you would like to see some genuine MathML then I can provide some
> examples
> on the web which would be free from corruption (since I'd just send you
> a link).  For example, there are quite a few matrices on this page:
>
> http://mathsnotes.math.ntnu.no/mathsnotes/show/homework+2011+8
>
> If you want more concise examples, those would be easy to produce.
>
> But with regard to the *final* format, I can't really help you, except to
> say
> that maybe you should stick to the programmers' motto: make it someone
> else's
> job.  I don't mean that *too* seriously, but by using MathML to represent
> your
> mathematics then you get to plug in to anything that can turn MathML into
> something more reasonable, rather than having to invent it yourself.
>
> Andrew
>



-- 
Richard G. Baldwin (Dick Baldwin)
Home of Baldwin's on-line Java Tutorials
http://www.DickBaldwin.com

Professor of Computer Information Technology
Austin Community College
(512) 223-4758
mailto:Baldwin at DickBaldwin.com
http://www.austincc.edu/baldwin/