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How Do I...  Please post site related problems on the  main talk page. i.e. Things not working as they should.

Underbrace and Overbrace
I'm having a problem with underbraces and overbraces in LaTeX. Normally,

\underbrace{a*a*\ldots*a}_{n \mbox{ terms}}

should give me an underbrace with "n terms" centered beneath it. Instead, it comes out looking like this:

$$\underbrace{a*a*\ldots*a}_{n \mbox{ terms}}$$

Clearly, the "n terms" is being interpreted as a subscript. The same thing happens with overbrace, except the "n terms" is interpreted as a superscript. What am I doing wrong? --Spoon737 19:36, 20 August 2008 (UTC)

For some reason some of the LaTeX commands don't work correctly, I'm not quite sure why that is but I'm trying to find out why, and then hopefully find a remedy. If anybody has MediaWiki experience, any help would be greatly appreciated. --Joe 20:34, 20 August 2008 (UTC)

A google search turns up http://www.haskell.org/haskellwiki/Help:Editing, which shows:

$$\begin{matrix} \underbrace{a*a*\ldots*a} \\{n times} \end{matrix}$$ which results in $$\begin{matrix} \underbrace{a*a*\ldots*a} \\{n \mbox{ times}} \end{matrix}$$ This page goes into detail on the sizing of the underbraces if you are doing them in tiers as well. I can't seem to make the subscript be a small character, but it's better than nothing. However, the problem is discussed more in detail here: http://svn.wikimedia.org/viewvc/mediawiki?view=rev&revision=17286 where they link to a supposed patch: http://svn.wikimedia.org/viewvc/mediawiki?view=rev&revision=17286 I don't know if you can install the patch, and if that would restore the old syntax. --cynic 19:48, 19 September 2008 (UTC)

I'll compile it and see if it works! --Joe 20:40, 19 September 2008 (UTC)

Got it fixed and working! Thanks Cynic! --Joe 14:41, 20 September 2008 (UTC)

Confusing fonts
Due to the choice of font for the "math" tag f'(z) and f(z) appear to be the same: $$f'$$ and $$f$$. The options appear to be not using apostrophes immediately after "f" (which seems extreme), increasing the font size used (either automatically or a prompt on the edit page) or changing the font. Or ignoring it.

example: penultimate line of proof in http://www.proofwiki.org/wiki/Liouville's_Theorem_(Complex_Analysis)

I hope this is more helpful than pedantic --HJM-B 22nd of February '10

That's a very good point. I hadn't noticed it since I have my display preferences set to always render as png (as I suspect do most of the heavy editors). The obvious solution from where I'm standing is just to set always render as png as the default for everyone, if that's doable. I don't know how much control we have over the html font, that's more of a server-side issue for Joe to look at, but if that's a simpler option than changing the default rendering, I would favor increasing the font size automatically since it looks like the html math text is on the small side anyway. --Cynic (talk) 00:10, 23 February 2010 (UTC)

My 2 cents worth is that it would probably be best to amend the page whenever such an awkwardness occurs by adding the "backslash space" to the math tags so as to force it to render as png. Something I haven't been doing because I always use "force png" and so can never remember to. --Matt Westwood 06:20, 23 February 2010 (UTC)

I'll see what I can do to tell everyone to force PNG --Joe (talk) 18:51, 23 February 2010 (UTC)

Eqn template
Just a note.

The delimiter $|$ doesn't seem to be valid in the eqn template, so I used \vert instead, but this behaves pretty weirdly, e.g.

is fine, but

is not.

Argh, also this:

{{eqn|l= |o=\leq |r= \frac{ \left\vert { a_n } \right\vert }{ n^{\sigma_0} } {{eqn|l= |o= = |r= \left\vert { \frac{a_n}{ n^{s_0} } } \right\vert

can't make it work at all. Linus44


 * Placing two }'s side-by-side will prematurely close {{eqn}} template. This has been a topic of discussion on the main page ... we're still looking for a fix. --Joe (talk) 15:23, 15 February 2011 (CST)


 * Ok, thanks Linus44 15:30, 15 February 2011 (CST)


 * You missed some closing braces

{{eqn|l= |o=\leq |r= \frac{ \left\vert { a_n } \right\vert }{ n^{\sigma_0} } }} {{eqn|l= |o= = |r= \left\vert { \frac{a_n}{ n^{s_0} } } \right\vert }}

{{eqn|l= \left\vert { \frac{a_n}{ n^s } } \right\vert |o= = |r= \frac{ \left\vert { a_n } \right\vert }{ n^\sigma } }} {{eqn|l= |o=\leq |r= \frac{ \left\vert { a_n } \right\vert }{ n^{\sigma_0} } }} <-- here {{eqn|l= |o= = |r= \left\vert { \frac{a_n}{ n^{s_0} } } \right\vert }} <-- and here {{end-eqn}} --Joe (talk) 15:32, 15 February 2011 (CST)


 * I tried 4 times to add the same reply but I kept getting a midair collision. Stroll on. --prime mover 15:35, 15 February 2011 (CST)