9.67.1 Top new questions this week

9.67.1.1 command \unit already defined

https://tex.stackexchange.com/landing/r/digest?cta=question&id=697873

The sequence 
\documentclass{amsbook} 
\usepackage{pst-eucl} 
\usepackage{prerex} 
\begin{document} 
\end{document} 
generates `command \unit already defined' error.  Either of the two packages by ... 
[pstricks]
 

asked by R. Gregory Taylor https://tex.stackexchange.com/landing/r/digest?cta=user&id=304489 Score of 5

answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 Score of 2

9.67.1.2 Spacing on text macros

https://tex.stackexchange.com/landing/r/digest?cta=question&id=697957

With the code 
\documentclass[11pt]{article} 
% --- PACKAGES --- 
\usepackage[margin=1in]{geometry} 
\usepackage[standard]{ntheorem} 
\usepackage{amsmath, amssymb, mathtools} 
\usepackage{enumitem, breqn} 
... 
[spacing]
 

asked by arz https://tex.stackexchange.com/landing/r/digest?cta=user&id=305602 Score of 5

answered by wipet https://tex.stackexchange.com/landing/r/digest?cta=user&id=51799 Score of 11

9.67.1.3 Why does a \catcode-changed underscore work in math mode also without \mathcode set to "8000?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=697819

Something is puzzling me... consider 
%\begingroup 
%\catcode`\_=13 
%\gdef_{\sb} 
%\endgroup 
\catcode`\_=11 
\def\foo_bar{Foo bar} 
\foo_bar\ $a_b$ 
\bye 
Uncommenting the commented code yields 
(One can ... 
[tex-core] [plain-tex] [catcodes] [mathcode]
 

asked by campa https://tex.stackexchange.com/landing/r/digest?cta=user&id=82917 Score of 5

answered by David Carlisle https://tex.stackexchange.com/landing/r/digest?cta=user&id=1090 Score of 4

9.67.1.4 Double or triple....exponent

https://tex.stackexchange.com/landing/r/digest?cta=question&id=697711

I have this MWE: 
\documentclass[a4paper,12pt]{article} 
\usepackage{amsmath,amssymb} 
\begin{document} 
Dato l'insieme non vuoto $A$ allora $(A^{c})^{c}$ A~.. uguale a: 
\end{document} 
with this output ... 
[math-mode] [superscripts]
 

asked by Sebastiano https://tex.stackexchange.com/landing/r/digest?cta=user&id=117876 Score of 5

answered by David Carlisle https://tex.stackexchange.com/landing/r/digest?cta=user&id=1090 Score of 4

9.67.1.5 Problem expanding math in arguments of en environment

https://tex.stackexchange.com/landing/r/digest?cta=question&id=697632

I want to redefine by hand a "restatable" environment for theorems. I have to do so because for some obscure reason the jloganal class (for the Journal of Logic and Analysis) mess it up: ... 
[math-mode] [environments] [expansion] [newtheorem] [expandafter]
 

asked by Quentin G https://tex.stackexchange.com/landing/r/digest?cta=user&id=305397 Score of 5

answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 Score of 1

9.67.1.6 Looking for a good Emacs/AUCTeX setup for LaTeX3

https://tex.stackexchange.com/landing/r/digest?cta=question&id=697954

I'm trying to switch my editor from vscodium (telemetry free VS Code) to Emacs. So far, I've installed AUCTeX and tried some things in a testdocument. For regular LaTeX code everything is fine. 
But ... 
[latex3] [emacs] [auctex] [auto-completion] [syntax-highlighting]
 

asked by lukeflo https://tex.stackexchange.com/landing/r/digest?cta=user&id=297560 Score of 4

answered by enkorvaks https://tex.stackexchange.com/landing/r/digest?cta=user&id=244233 Score of 4

9.67.1.7 How to make a complex chemical diagram

https://tex.stackexchange.com/landing/r/digest?cta=question&id=697690

I did everything possible to recreate this picture but I got stuck. 
My best result is SOOO far from perfect. 
\documentclass[border=1cm]{standalone} 
\usepackage{chemfig} 
\usepackage[utf8]{inputenc} %... 
[tikz-pgf] [diagrams] [chemfig] [chemistry]
 

asked by Eth\234EthDegreeEth\272N~\201Eth,Eth\274 Eth\236Eth\264Eth\275Eth\276N~\200EthDegreeEth>> https://tex.stackexchange.com/landing/r/digest?cta=user&id=300395 Score of 4

answered by CrocoDuck https://tex.stackexchange.com/landing/r/digest?cta=user&id=134993 Score of 2