Moodle in English: Hiding the DragMath button

Hiding the DragMath button

by Ian Wild - Tuesday, March 10, 2009, 9:22 PM

Hi all,

I don't know if this is the right place to bring this up but I've just been re-reading the Moodle docs regarding DragMath (i.e. here) and we seem to be pretty harsh when it comes to those who want to be able to hide the DragMath button in the HTML editor.

There is, in fact, good reason (certainly in the UK) why you would want to allow this: often in an "education district" (e.g. counties or cities) Moodles are maintained centrally and, for the sake of convenience, any modules and plug-ins requested by one school are installed in *all* the Moodles. Some of those schools don't want all of the buttons in the editor (DragMath being a case in point) and admins based in a particular school certainly do hide buttons they don't want to bamboozle young children (and teachers big grin

) with.

What I am trying to say is that in the UK this is an important feature. Anyone any objections to me modifying the docs to reflect this?

Cheers,

Ian.

Re: Hiding the DragMath button

by Marc Grober - Wednesday, March 11, 2009, 3:34 AM

Hi Ian,

I actually am preparing a bit of a rewrite based on my decision to use the zip I placed in the tracker as opposed to CVS.... and so as to make sure I don;t get my paragraphs mashed too badly, I went ahead and made some changes to address your concerns as part of the rewite I was planning, and inserted those changes ahead of schedule........

Average of ratings: -

Re: Hiding the DragMath button

by Ian Wild - Tuesday, April 14, 2009, 6:40 AM

Hi Marc,

Sorry for the late reply on this one (err... at over a month blush

). Thanks for making those changes. I'm just thinking about potential changes to the docs regarding both the algebra and TeX filters. I keep being asked if there is a definitive syntax list for both of those filters. Obviously there's http://www.forkosh.com/mimetexmanual.html for mimeTeX but there doesn't seem to be anything similar for the algebra filter. Or is it that I just haven't found it yet?

Thanks again,

Ian.

Average of ratings: -

Re: Hiding the DragMath button

by Marc Grober - Tuesday, April 14, 2009, 7:52 AM

<LOL>
When is tex not tex.....
</LOL>

There are lots of sources on the net vis-a-vis syntax for tex, such as this one,
http://www.personal.ceu.hu/tex/cookbook.html
and any quick search will find quite a few (see e.g. http://www.google.com/search?q=latex+tutorials)

But there are also quite a few "implementations" and there are differences.... and of course, one needs to differentiate between the syntax of the software providing the implementation and the syntax for the tex its providing....

Perhaps the best rule as far as the actual text expressions to be parsed by the tex application is try what one might argue is "standard" and then post to a forum when you become disgruntled ;=}

This:
$$\begin{eqnarray*}
2x^2 + 3(x-1)(x-2)&=&2x^2 + 3(x^2-3x+2)\\
&=& 2x^2 + 3x^2 - 9x + 6\\
&=& 5x^2 - 9x + 6
\end{eqnarray*}$$

Obviously doesn't work though this:
http://www.artofproblemsolving.com/LaTeX/AoPS_L_BasicMath.php#eqnarray
suggests it should.

Of course to make matters more confusing, Moodle uses a "filter" which employs the doubledollar signs which arguably add to the confusion (see comments here:http://en.wikibooks.org/wiki/LaTeX/Mathematics
by way of discussion.....

Of course there si lots o discussion as gar as using tags versus tokens, spans, etc when trying to embed and parse tex in an online doc....

Average of ratings: -

Re: Hiding the DragMath button

by Ian Wild - Wednesday, April 15, 2009, 7:09 AM

Hi Marc,

You're right: it does really all depend on the TeX implementation. Do you know how the algebra filter actually works? I appreciate it converts "asciimath" to TeX but are there any limitations on what it can convert? Do you know if this is documented anywhere?

I was also interested to see that mimeTeX has now been superseded by mathTeX. The only problem I can see is that mathTeX can only be deployed on Unix-like systems. That's certainly a limitation in the UK where we have quite a few schools using Windows and Mac servers.

Cheers,

Ian.

Average of ratings: -

Re: Hiding the DragMath button

by Marc Grober - Wednesday, April 15, 2009, 10:35 AM

As I understand it, the algebra filter is based on perl scripts (see perl module here: http://cvs.moodle.org/moodle/filter/algebra/AlgParser.pm?revision=1.5) that parses text in the alegbra tokens @@\sqrt(4)@@ and converts to tex. This is from the associated filter.....

// NOTE: This Moodle text filter converts algebraic expressions delimited
// by either @@...@@ or by <algebra...>...</algebra> tags
// first converts it to TeX using WeBWorK algebra parser Perl library
// AlgParser.pm, part of the WeBWorK distribution obtained from
// http://webhost.math.rochester.edu/downloadwebwork/
// then converts the TeX to gif images using
// mimetex.cgi obtained from http://www.forkosh.com/mimetex.html authored by
// John Forkosh john@forkosh.com. The mimetex.cgi ELF binary compiled for Linux i386
// as well as AlgParser.pm are included with this distribution.
// Note that there may be patent restrictions on the production of gif images
// in Canada and some parts of Western Europe and Japan until July 2004.

arguably, this filter could as easily be replaced by LaTexML (see http://dlmf.nist.gov/LaTeXML/) which may benefit (or suffer) because of its association with NIST.... In fact I initially thought that this was the way of the future until I bumped into asciimath, in no small part because I have experience programming in perl, not php. I have not turned Mauno on to this (uh oh!!) for fear he will loose focus ;=} LOL

The alg filter still converts to tex and then to gifs, and falls back to mimetex. One could argue that it would make most sense to dump the alg filter, replace it with LaTexML and then Moodle has builtin filters to do either tex to gif or tex to xml, but that might agravate the algebra filter users... though you'd have to look through the tables in the perl module to see if they'd really notice any diff..... my guess is that if swapped out the algebra filter with asciimathml, few would note any diff.....

But I digress .....

the alg filter does not convert asciimath to tex in the sense of asciimathml.... it is converting an ascii text expression to tex, whereupon it is converted to gifs (not pngs....) unless the tex software is awol in which case mimetex is invoked...

As note above.... you can see the tables much as you would see the asciimathml tables in the algparser module.... If you ask me why anyone would use algparser instead of tex I really can't answer, but the discussion of alg filter syntax in Moodle can be found here: http://moodle.org/mod/forum/discuss.php?d=5402

Mathtex has been around for awahile, but when it comes to packaging mimetex is a wider sell (its those MS WIdnows people again, don't you know.... whoops... you deal with Becta so you DO know - LOL) Mauno has been playing with Live Tex as well and I have played around with MathTran.... BUT, OS X IS a unix server, so you only have problems if you insist on working with an OS that is sold by a company arguably without scruples (like BAE or Siemen's , LOL) But mimetex IS fast and easy, and is much more comprehensive at the moment than MathTran (which we tested out as a fallback system for asciimathml as well.)

If I only had a proper job I'd probably talk my employer into letting me do the latexml project ....

Average of ratings: -

Mathematics tools

Hiding the DragMath button