Add math support via mathjax

[alanocallaghan]

I'd like to add math support for a couple of lessons I'm going to be working on in some fashion or other. This is a simple-ish way to do it.

atm I'm stopping mathjax from being in every page by having a math: true|false field in _config.yml. If this is a decent solution I'll make a PR for the template to add a field. If the field isn't defined it defaults to old behaviour of not including it. Otherwise it could be a frontmatter for each page, rather than each site, or possibly both (ie, only if site.math && page.math)

Could switch this to doing something similar with katex if that's preferred, I'm just used to mathjax. I believe there's some way to get serverside rendering with katex, but this is probably tricky with github-pages

Example: https://alanocallaghan.github.io/latex-novice-typesetting/01-introduction/index.html
https://github.com/Alanocallaghan/latex-novice-typesetting/blob/gh-pages/_episodes/01-introduction.md

[fmichonneau]

Thanks for this PR!

Could you please open it against https://github.com/carpentries/styles? (once it's merged there, we can bring it to the remote theme). We have an old issue about this here: carpentries/styles#154

Several people have mentioned that KaTeX was "better" than MathJax, so maybe go for that?

Given that we want to be able to support offline rendering of the lessons, we'd need to include the katex files in the repo.

I think that a per-page inclusion would make sense (with page.math).

[alanocallaghan]

What is the styles repository, and what do you mean by remote theme

[fmichonneau]

the styles repository is here: https://github.com/carpentries/styles it's the main repository we use for our lessons. This repository only contains the files for the lessons that use the remote theme.

…

On Wed, Apr 14, 2021 at 4:10 PM Alanocallaghan ***@***.***> wrote: What is the styles repository, and what do you mean by remote theme — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <#13 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABJ7PSVRYTJCP7BJ4VC7C43TIXZCNANCNFSM42JXFHBA> .

[alanocallaghan]

I am somehow failing to understand why you would maintain two parallel versions but that's outside the remit of this PR