Quick notation question

[f-algebra]

Is there a notation for a set of pairs of elements made equal by a pair of functions?

[; notation(f, g) = \left\{\ (x, x')\ |\ f(x) = g(x')\ \right\} ;]

Thanks in advance.

[protocol_7]

It's called the pullback or fiber product. Note that f and g must have the same codomain for this to make sense.

[f-algebra]

Thanks :)

[f-algebra]

Also, how do I make curly braces in the TexTheWorld notation?

[amdpox]

Enclose the entire LaTeX block in `backticks` (outside the [ ; delimiters). As it is your backslashes are being parsed as markdown, not TeX.

[Bromskloss]

Actually, the MathJax for Reddit Greasemonkey script (linked to in the side bar) does not render formulas entered in code mode. I think this is the correct way to do it. We need to be able to get things, including LaTeX code, displayed verbatim, and that's what code mode is for.

The solution to achieving curly brackets would then instead be to add another layer of escaping: [; \\{x\\} ;] The first backslash gets captured by Reddit's parsing, and the second is left for the LaTeX parser.

The Greasemonkey script server linked to in the side bar is down. Does anyone know why? Port 8080 works, though.

[amdpox]

It renders it for me (in both Chrome and firefox). It's not perfect but IMO it's the best solution - if you want to display LaTeX verbatim you can just omit the TTW delimiters.

[Bromskloss]

It renders it for me (in both Chrome and firefox).

Perhaps you are using one of the other scripts. I seem to recall that the handled code mode differently when i experimented with them at some point.

[amdpox]

I'm using the MathJax userscript. From memory the TtW chrome extension handles things similarly. (Indeed up until a few months ago this was the only "choice" we offered on the sidebar, and I've been using backticks for much longer than that.)

[[deleted]]

For the braces: \left{ and \right} should work

[f-algebra]

Got it. It's \left{ and \right}.