8.35.1 Top new questions this week

8.35.1.1 Why does (my user-defined) command for superscript (inverse) fail next to a prime (quotation) symbol?
8.35.1.2 How to put figures into longtable
8.35.1.3 Find out if a figure is positioned h, t, b, or p
8.35.1.4 tcolorbox calculation of the length of the title gets wrong for 10 and 100
8.35.1.5 Why can't I use <some macro> inside the argument of <some other macro>?
8.35.1.6 Conditional statements in TikZ
8.35.1.7 How to Specify Outline Thickness and Fill/Outline Colors?
8.35.1.1 Why does (my user-defined) command for superscript (inverse) fail next to a prime (quotation) symbol?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=646157

Minimum working example (I will refer to the lines based on the first letter A-E): 
\documentclass{article} 
\newcommand{\inv}{^{-1}} 
\begin{document} 
$A^{-1}$ 
$B\inv$ 
$C'^{-1}$ 
% $D'_1^{-1}$ % fails 
% $... 
[math-mode] [macros] [superscripts]
 
asked by Benjamin Wang https://tex.stackexchange.com/landing/r/digest?cta=user&id=271457 Score of 8
answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 Score of 6
8.35.1.2 How to put figures into longtable

https://tex.stackexchange.com/landing/r/digest?cta=question&id=645973

Below is my code where I'm trying to put figures into longtable. I'm wondering how can I decrease the spaces between figures (columns) and how can I stretch the figures to both margins? 
\documentclass[... 
[floats] [longtable]
 
asked by Math122 https://tex.stackexchange.com/landing/r/digest?cta=user&id=222358 Score of 6
answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 Score of 6
8.35.1.3 Find out if a figure is positioned h, t, b, or p

https://tex.stackexchange.com/landing/r/digest?cta=question&id=645610

Is there a way to find out and use the positioning choice (here, top, bottom, page) made for some figure? 
Please spend a few minutes to admire 
\edef\mypos{\thepositioningchoicethatwasusedfor{myfig}} 
\... 
[floats] [positioning]
                                                                                  

                                                                                  
 
asked by Hagen von Eitzen https://tex.stackexchange.com/landing/r/digest?cta=user&id=25343 Score of 6
answered by John Kormylo https://tex.stackexchange.com/landing/r/digest?cta=user&id=34505 Score of 3
8.35.1.4 tcolorbox calculation of the length of the title gets wrong for 10 and 100

https://tex.stackexchange.com/landing/r/digest?cta=question&id=645593

I use tikz and tcolorbox to create boxes for theorems. I calculate the length of the title in order to cut the frame. Everything works until the counter gets to 10 or 100, the calculation of the ... 
[tikz-pgf] [tcolorbox]
 
asked by Flowt https://tex.stackexchange.com/landing/r/digest?cta=user&id=270421 Score of 6
answered by Jinwen https://tex.stackexchange.com/landing/r/digest?cta=user&id=194994 Score of 4
8.35.1.5 Why can't I use <some macro> inside the argument of <some other macro>?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=645995

I have some macro X and Y, which works well when used independently. However, when I try to put one inside another, it results in some error. 
Why is that the case and how can I fix it? 
Note: this is ... 
[macros] [verbatim] [expansion] [programming]
 
asked by user202729 https://tex.stackexchange.com/landing/r/digest?cta=user&id=250119 Score of 5
answered by user202729 https://tex.stackexchange.com/landing/r/digest?cta=user&id=250119 Score of 8
8.35.1.6 Conditional statements in TikZ

https://tex.stackexchange.com/landing/r/digest?cta=question&id=645649

I'm trying to use if in my TikZ picture. For example, I want to draw a point at the origin only if 1 < 2. I can do it, for example, like this: 
\begin{tikzpicture} 
if 1 < 2 then 
\fill ... 
[tikz-pgf]
 
asked by Alexey Ismagilov https://tex.stackexchange.com/landing/r/digest?cta=user&id=171124 Score of 5
answered by Sandy G https://tex.stackexchange.com/landing/r/digest?cta=user&id=125871 Score of 5
8.35.1.7 How to Specify Outline Thickness and Fill/Outline Colors?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=645457

This question asks for an extension of this answer. Consider the code: 
\documentclass[12pt]{book} 
\usepackage{xcolor} 
\usepackage{cabin} 
\usepackage{scalefnt} 
\input pdf-trans 
\font\f=qx-lmr10    at ... 
[fonts] [boxes] [letters] [box]
 
asked by mlchristians https://tex.stackexchange.com/landing/r/digest?cta=user&id=192836 Score of 5
answered by David Purton https://tex.stackexchange.com/landing/r/digest?cta=user&id=87678 Score of 6