Navigation

This site is at beta test stage! Comments are welcome. Contributions are sought and will be published with acknowledgement.

 

home page

quick overview

 

flow chart

site index

contact us

site use

 

contribute now!

 

©Liddy Nevile

Acknowledgements

 

Making mathematics notation accessible


What is the problem with what people do today?

Today, people often place mathematical notation on the web in the form of an image. As explained elsewhere, such notation is not accessible, in the real sense, to anyone although it can be viewed by people with graphical browsers.

Let us consider the following expression:

a3+b3=(a+b)(a2-ab+b2)

Imagine it is not text on the page but appears as an image inserted into the text. Imagine there is an alt tag for the image and maybe a long description of what it contains. The alt tag, or long description, might say one or more of the following,

But there will most probably still be difficulties for some users.

.


EzMath

An older but perhaps useful approach for short term work is to use the EzMath editor - free and downloadable for Windows 95/NT from http://www.w3.org/People/Raggett/ezmath1_1.zip

As the authors, Dave Raggett (dsr@w3.org), Davy Batsalle (batsalle@email.enst.fr) say (see http://www.w3.org/People/Raggett/EzMath/):

"W3C's MathML provides two sets of tags, one concerned primarily with presentation, and the other with the meaning of mathematical expressions. MathML aims to provide a low level format for machine to machine communication. It is much more verbose than EzMath, and is not intended for direct editing.

The EzMath editor also provides support for marking up expressions in MathML's content tags. To do this, you simply change the clipboard format to MathML."

The advantage of using EzMath is that you can make editable maths for use on the broewser screen. the disadvantages include that it is an incomplete set of maths expressions that can be handled, for instance sometrigonometric expressions may not be possible, nor are a number of other expressions. Writing EzMath is something that can be done fairly easily by specifying how the expression is understood in a form that makes it fairly easy to author.

Some examples are offered:

ax^2+bx+c=0
integral from 0 to pi of sin ax wrt x
limit as x tends to infinity of function f(x)
matrix M = matrix (1,2;2,1)

and

a^m over a^n = either a^{m-n} when m > n or 1 when m = n or 1 over a^{n-m} when m < n

which, when displayed using EzMath, appears as:

It is possible that EzMath is suitable for screen readers.


Last updated: 8 March 2002