6.32.1 Top new questions this week

6.32.1.1 What are some typical LuaTeX gotchas?
6.32.1.2 It is possible to use a diagram in an expression?
6.32.1.3 arXiv is not word-wrapping long bibliography entries the way Overleaf and my local installation do, for precisely the same Minimum Working Example
6.32.1.4 Changing sum and product symbols
6.32.1.5 IBM Plex text fractions with ConTeXt
6.32.1.6 How to get this symbol (looks like a T or J)
6.32.1.7 How to centre a matrix?
6.32.1.1 What are some typical LuaTeX gotchas?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=550673

The interaction of TeX and Lua can be quite delicate at times.  While the former has category codes and tokens, the latter has escape sequences and datatypes.  Mixing the disparate concepts of these  ... 
[macros] [errors] [luatex] [expansion] [lua]
 
asked by Henri Menke https://tex.stackexchange.com/landing/r/digest?cta=user&id=10995 24 votes
answered by Henri Menke https://tex.stackexchange.com/landing/r/digest?cta=user&id=10995 23 votes
6.32.1.2 It is possible to use a diagram in an expression?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=550425

I'm watching a video series about category theory, and it shows the following kind of notation on several occasions: 
I like taking notes in LaTeX, so I am wondering if there is an easy way to typeset  ... 
[tikz-pgf]
 
asked by j4nd3r53n https://tex.stackexchange.com/landing/r/digest?cta=user&id=140504 8 votes
answered by Vincent https://tex.stackexchange.com/landing/r/digest?cta=user&id=201628 10 votes
6.32.1.3 arXiv is not word-wrapping long bibliography entries the way Overleaf and my local installation do, for precisely the same Minimum Working Example

https://tex.stackexchange.com/landing/r/digest?cta=question&id=550848

After extensive discussion with Barbara Beeton in the chat room, and later with David Carlisle in the same place, I was recommended by both to write my question here; it has just taken some hours to  ... 
[bibliographies] [formatting] [natbib] [revtex] [arxiv]
 
asked by user1271772 https://tex.stackexchange.com/landing/r/digest?cta=user&id=14527 7 votes
answered by Ulrike Fischer https://tex.stackexchange.com/landing/r/digest?cta=user&id=2388 2 votes
6.32.1.4 Changing sum and product symbols

https://tex.stackexchange.com/landing/r/digest?cta=question&id=550656

I've been searching for answers, found a couple but could not make them to work in my particular situation. If there is a general procedure to do the change, I'd be glad to read it. 
Is there a way to  ... 
[xetex] [symbols] [math-operators]
 
asked by Anibal https://tex.stackexchange.com/landing/r/digest?cta=user&id=218934 7 votes
answered by Davislor https://tex.stackexchange.com/landing/r/digest?cta=user&id=61644 7 votes
6.32.1.5 IBM Plex text fractions with ConTeXt

https://tex.stackexchange.com/landing/r/digest?cta=question&id=550475

I want to typeset text fractions with potentially arbitrary text instead of just numbers. A solution was presented here and this is my ConTeXt implementation: 
\usetypescriptfile[ibmplex] 
... 
[luatex] [context]
 
asked by blaze https://tex.stackexchange.com/landing/r/digest?cta=user&id=76090 6 votes
answered by Wolfgang Schuster https://tex.stackexchange.com/landing/r/digest?cta=user&id=33961 5 votes
6.32.1.6 How to get this symbol (looks like a T or J)

https://tex.stackexchange.com/landing/r/digest?cta=question&id=550505

I've tried drawing this symbol in Detexify, but with no luck: 
It's not \mathcal{TJ}: $\mathcal{TJ}$ or \mathscr{TJ}: $\mathscr{TJ}$. 
I'm guessing it's a T from context in the textbook.  It has the  ... 
[symbols]
 
asked by Tom Hale https://tex.stackexchange.com/landing/r/digest?cta=user&id=135143 6 votes
answered by Denis https://tex.stackexchange.com/landing/r/digest?cta=user&id=49497 13 votes
6.32.1.7 How to centre a matrix?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=550229

I have inserted a matrix into my LaTex article using the following code: 
For a $3 * 3$ grid, given as 
\begin{bmatrix} 
a & b & c \\ 
d & e & f \\ 
g & h & i \\ 
\end  ... 
[math-mode] [horizontal-alignment] [matrices] [article] [atom]
 
asked by Gill https://tex.stackexchange.com/landing/r/digest?cta=user&id=218712 5 votes