Can we have MathJax please to format mathematical formulas?

Question

Other SEs can format mathematical formulas in a way called mathjax. It makes fractions and equations and pretty much everything mathematical look good.

It's a subset of tex for the internet and it makes those formulas (as ugly as their content may be) look rather pretty. (that is, the prettiness of typeset text)

I agree that this is not the most important thing, because formulas only show up occasionally in photography, but they still do show up from time to time.

It shouldn't be hard to implement either, because the functionality already exists.

Here are some example posts in which I wanted to use it and which in turn caused me to ask this question here:

• This question involves optical formulas. This seems to be the most obvious use case, because photography is in part applied physics.
• This great question about different terms used by different manufacturers could benefit from using tables, ... (Edit: Markdown tables were implemented in 2020 (c.f, scottbb's answer below).

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If MathJax were enabled for Photo-SE, the standard delimiter of $ ... $ would be an issue (because we often mention gear prices), so we could instead use delimiters of \$ ... \$ for inline MathJax. (The $$ ... $$ block-level MathJax delimiters is fixed).

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Answer 1

Another "better late than never" classic... :)

MathJax has been enabled, using \$ for inline delimiters as suggested. Please let us know if you see any issues.

Answer 2

100% in favor of enabling MathJax.

1. 31 Stack Exchange sites support MathJax (https://meta.stackexchange.com/a/216607/175991)
2. Tables: LaTeX arrays can be used for table data. (ex: https://rpg.stackexchange.com/a/67007/8083) (Markdown tables have been implemented as of December 2020)
3. Load times: this is Photography.SE. We often have images on our pages. Those take load time as well.
4. Several people unanimously upvoted having TeX support in our Markdown as far back as 2011.

Addressing the concept of only loading MathJax if necessary: unfortunately, that's not practical. MathJax is a client-side JavaScript library. This part of the issue has been addressed many times on other SE sites. For SE sites, it's all or nothing. But we can choose to turn it on. So, let's.

Questions that would benefit from having MathJax enabled

Out of the top 200 voted questions on the site, the formatting and readability of the following questions would benefit from having MathJax enabled:

1. What is the "exposure triangle"? — this barely needs better formatting of lots of fractions, but if they were cleaned up with MathJax, some of the answers would read better.
2. How do I generate high quality prints with an ink jet printer? — 9 equations, 2 tables in 2 answers.
3. How do I set the proper exposure for nighttime moon photos?
4. How to get the best results for landscape and stars photographs?
5. What does f-stop mean?
6. What is a "diffraction limit"?
7. What exactly determines depth of field?
8. Why do light sources appear as stars sometimes?
9. How do I convert lens focal length (mm) to x-times optical zoom?
10. Is there a general formula for image size vs. print size?
11. How can I get dramatic shallow DOF with a kit lens?
12. How can I calculate what the effect of an extension tube will be?
13. I'm hoping to prove this distance to camera equation:
14. Is the formula for object image size given focal length, etc. independent of sensor size?
15. How do I calculate the distance of an object in a photo?
16. Calculation for getting dimension of object in image not working
17. Can we measure size of an object using EXIF data from a photo?

Answer 3

I'm not sure if tables are part of MathJax or not.

For mathematical formulas, standard whitelisted tags work:

M = (d_i - f) / f

ho is the height of the object
do is the distance from the lens to the object
f  is the focal length
di is the distance from the lens to the image

Yea, the background kind of sucks here for code format so I tossed it in a block quote. The above text is:

> <code>h<sub>o</sub></code> is the height of the object  
<code>d<sub>o</sub></code> is the distance from the lens to the object  
<code>f<sub>&nbsp;</sub></code> is the focal length  
<code>d<sub>i</sub></code> is the distance from the lens to the image

Consider also reading There's seriously no reason why LaTeX markup via MathJax shouldn't be enabled on SO where Nick gives demonstrable numbers of how long it takes to load MathJax on the page load. Even with no Mathjax on the page, it takes an additional 0.3 seconds for the page to load. If there is mathjax in the content, it takes another second for it to load.

MathJax also significantly impacts the editing experience by causing the preview to be reloading the text and attempting to re-render it with MathJax each key click.

Answer 4

While this won't help with writing formulas, at least as far as simple tables go, as of early December 2020, the Stack Exchange network has implemented GitHub-flavored Markdown table syntax support.

So for the example in the question, the following syntax...

|       | stabilisation | mount        |
|-------|---------------|--------------|
| Canon | IS            | EF, EF-S,... |
| Nikon | VR            | AI, AI-S...  |
| Sony  | OSS           | E            |

... will produce this table:

	stabilisation	mount
Canon	IS	EF, EF-S,...
Nikon	VR	AI, AI-S...
Sony	OSS	E

You can't do anything complex with the GHF Markdown table syntax, such as combining/spanning cells vertically or horizontally. But for basic tabular data, it can sure help.

Answer 5

I came to the conclusion that the best thing would be to allow mathjax only if necessary.

Ideally, one would have to click some checkbox in the editor to explicitly include it. This checkbox would remind the user that this has some drawbacks on the performance and should only be used if necessary.

I think this is best, because while it is true that it is rarely needed, it is very useful in those rare occasions.