6.31.1 Top new questions this week

6.31.1.1 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 14 votes

answered by Henri Menke https://tex.stackexchange.com/landing/r/digest?cta=user&id=10995 14 votes

6.31.1.2 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 7 votes

answered by Vincent https://tex.stackexchange.com/landing/r/digest?cta=user&id=201628 8 votes

6.31.1.3 How to cancel the root but not the expression inside it?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=549809

I wanted to cancel the root of an expression like this 
\documentclass{article} 
\usepackage{cancel} 
\begin{document} 
\[\cancel{\sqrt{\left(a+b+c+d+f+g+h+e\right)^{\cancel{2}}}}\] 
\end{document} 
I'm  ... 
[cancel] [root]
 

asked by Concept7 https://tex.stackexchange.com/landing/r/digest?cta=user&id=41168 6 votes

answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 12 votes

6.31.1.4 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 5 votes

answered by Davislor https://tex.stackexchange.com/landing/r/digest?cta=user&id=61644 5 votes

6.31.1.5 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 5 votes

answered by Denis https://tex.stackexchange.com/landing/r/digest?cta=user&id=49497 11 votes

6.31.1.6 Which LaTeX packages do really support 3D points manipulations, etc?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=549836

First consider the following example for illustration purposes. The objective is to draw the shortest line segment from the point H to the plane BDE. The prism ABCD.EFGH has AB=AD=5\sqrt{2} and AE=12.  ... 
[tikz-pgf] [pstricks] [asymptote] [metapost] [technical-drawing]
 

asked by Too Fat Man No Neck https://tex.stackexchange.com/landing/r/digest?cta=user&id=87876 5 votes

answered by user187802 https://tex.stackexchange.com/landing/r/digest?cta=user&id=187802 2 votes

6.31.1.7 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 4 votes