Writing mathematics in real time for lectures using Latex

I am supposed to hold tutorial sessions for an undergraduate course in calculus. But the software provided by the university is not good at all. I saw the question suggesting to use Ziteborad but it is not what I am looking for.

I am searching for some real time Latex compiler which would allow me to write what I am explaining on the fly without waiting to compile each time I add a sentence or a formula. Stack Exchange has an incorporated MathJax compiler whose functionality is similar to what I would like. Is there not a program or browser page which visualizes what I write in Latex code on a big page easy to present via screen sharing?

• Maybe also ask at tex.stackexchange.com ? – Gerald Edgar Nov 2 at 18:09
• Would it not be simpler to hand write using a touchscreen device? – mweiss Nov 3 at 0:19
• @mweiss Personally, it took me a while before my tablet handwriting was anywhere near as good as my pen or chalkboard handwriting. (It's the low friction.) My $\Sigma$s looked like 2's with a line on top. I can see why someone would want something nice and legible. – Adam Nov 3 at 0:30
• @Adam I had the same experience until I got an Apple Pencil and one of the newer iPads that supports it. It was a game-changer -- as natural as writing on paper or chalkboard. – mweiss Nov 3 at 1:05
• Considering a tablet was my first idea: the problem is that I bought a Samsung Galaxy Tab s7 but I could not write more than 20 minutes due to eye strain. I have a very peculiar condition so it happened even if I read several reviews stating they had no similar issues. I know that the Ipad screen adopts a different technology from Samsung but I am not sure I would not get any eye strain. – N.B. Nov 4 at 11:43

I believe Overleaf would be your best bet. I am currently taking a class right now where the lecturer writes up the contents of the lecture using overleaf and it's very feasible. Even though you don't want to wait around for it compile, Overleaf renders documents pretty fast, and can render without you needing to press the command to do so. I'd say there's also the added benefit that your students can see the latex code as it's being written so they can pick up how to use latex if they don't know it already.

• If I may add one thing, Overleaf has a "fast compile mode" which is faster than the regular real-time compilation. The only set back is that it does not process figures/images. – aziiri Nov 26 at 22:00

You might find jupyter notebooks useful, especially if you use either the Sympy or Sage computer algebra systems. These notebooks allow you to enter mathjax enabled markdown on the fly; which can also be generated as the output of sage and sympy. For example, sympy shows a live example session on their site:

Graphs are also straightforward, and can be quick to generate with some practice.

• Jupyter seems like massive overkill if all they want is math rendering. – Ben Crowell Nov 4 at 0:42
• True, but, on the other hand, if you start using Jupyter, there are a lot of nifty things you can add to a math lecture: examples, plots, ... – Federico Poloni Nov 18 at 21:45

I use Lyx as my LaTeX "word processor", and it's really good at real-time interpretation. You can build your statements using a GUI sort of like Microsoft Equations back in the day or you can just type straight LaTeX. The creators insist that it isn't WYSIWYG, but the distinction between WYS on the screen and WYG out of a printer is insignificant from my perspective.

I have used Microsoft OneNote 2016 (plus screensharing software) for online tutorial sessions in number theory during the past year. It has worked very well and I will continue to use it.

You can enter plain text just like in Microsoft Word and switch to Math mode by pressing a shortcut (["Alt" + "+"] in my case (German), but it might also be ["Alt" + "="] or something else). In Math mode, you can essentially write LaTeX code which is transformed into mathematics upon pressing space. (This works similarly to autocorrection.) Some experience is required to use this swiftly and there are some differences to LaTeX (e.g. round brackets are used for logical grouping, not curly brackets). It is also not as powerful as LaTeX, but you can do all kinds of basic mathematics like greek letters, basic relational symbols, integrals, summation symbols, matrices etc. You can also add, remove and change math commands (go to Options>Proofing>Autocorrect options). For example, I added lots of LaTeX commands without backslashes for myself, so I can write "alpha" instead of "\alpha" to get $$\alpha$$.

An example from my tutorial sessions:

The formatting is not as great as in LaTeX, obviously.

Further remarks:

1. The same math functionality is available in Microsoft Word, but OneNote is free and supports infinitely large pages. Further, if you have a touchscreen device with a pen, you can also make drawings next to your text as needed.
2. Make sure you use OneNote 2016, not OneNote for Windows 10. These are two similar versions of OneNote (both are freely available), but OneNote 2016 is better suited for this usage.
• "The formatting is not as great as in LaTeX, obviously." Bingo. Also, and perhaps more importantly, there is the ever present problem of version creep. LaTeX is great in part because we need not worry about some business changing the rules of the game for their best interests. Of course, for disposable conversations, my objections are less salient. – James S. Cook Nov 9 at 1:45
• @JamesS.Cook Well, the formatting is still good imo, just not great. And I would argue that online tutorial sessions are "disposable conversation" in the sense that you will not touch them after the class finishes (except for possible corrections). Of course, students will use them as learning material, but version compatibility is not an issue here because you can export a pdf. – Torben Wiedemann Nov 10 at 13:31

It's not free (yet), but it is the only true "on the fly" WYSIWYG Windows LaTeX compiler that I know: BaKoMa TeX (http://www.bakoma-tex.com/menu/about.php).

The project is gathering \$ to make the software public domain.

I was using Overleaf for my classes, and switched over to Notion (for other reasons as well). One of Notion's amazing abilities is to render LaTeX in real-time, both in-line or as a block equation (which you can set through Notion's properties and switch back if necessary).

You can also just paste images and drag-and-drop every block everywhere. I heartily recommend it.

Bonus: Notion has awesome database capabilities which can also help you track your problem-sets and all sorts of course-related materials.