incompatibilityphysicssymbols
Using \div gives me divergence sign instead of division (รท), for sure inside of math mode.
\documentclass[conference]{IEEEtran}
\usepackage{amsmath,amssymb}
\usepackage{physics}
\begin{document}
$ 1 \div 2 $
\end{document}
returns back ;
As far as I know the problem is physics package and without it everything is ok, but I need it.
I was able to use my scalerel package to hopefully give you what you want (scalerel was just sent to CTAN today, so until it propagates, you can find the style listing at How to horizontally merge two symbols?).
Using that package's features, my first cut was to create a command \myabs, which places abs bars around anything. It will stretch the size of the bars exactly to the argument. The downside of this first attempt is that you may have preferred the bars to extend a bit above and below the object being surrounded (addressed later in this answer). Here's the code for the first approach:
\documentclass{article}
\usepackage{scalerel}
\usepackage{mathtools}
\begin{document}
% [METHOD USED IN ORIGINAL QUESTION CODE HERE, REMOVED FROM THIS LISTING]
\newcommand\myabs[1]{%
\setbox1\hbox{$#1$}%
\stretchrel{\lvert}{\usebox1}\stretchrel*{\lvert}{\usebox1}%
}
\[ \myabs{\vec{k}}~~\myabs{\vec{x}}~~\myabs{\vec{A}}~~\myabs{\vec{q}} \]
\end{document}
and here's the output, as compared to your original
However, to answer ralfix's request to extend the vertical line a bit above and below the surrounding object, I just used the \addvbuffer routine from the verbatimbox package, setting the top and bottom add-on to 2pt:
\documentclass{article}
\usepackage{scalerel}
\usepackage{mathtools}
\usepackage{verbatimbox}
\setlength\boxtopsep{2pt}
\setlength\boxbottomsep{2pt}
\newcommand\myabs[1]{%
\setbox1\hbox{$#1$}%
\setbox2\hbox{\addvbuffer{\usebox1}}%
\stretchrel{\lvert}{\usebox2}\stretchrel*{\lvert}{\usebox2}%
}
\begin{document}
\[ \myabs{\vec{k}}~~\myabs{\vec{x}}~~\myabs{\vec{A}}~~\myabs{\vec{q}} \]
\end{document}
But egreg commented that the height of the abs bar should not change with the argument. If that is the preferred embodiment of abs, then scalerel can fix that too:
\documentclass{article}
\usepackage{scalerel}
\def\lvert{|}
\begin{document}
METHOD 2: FIXED EXTENT
\newsavebox\mybox
\savebox{\mybox}{$\stretchrel*{|}{\rule[-.6ex]{0ex}{3ex}}$}
\def\myabs#1{\usebox\mybox#1\usebox\mybox}
\[ \myabs{\vec{k}}~~\myabs{\vec{x}}~~\myabs{\vec{A}}~~\myabs{\vec{q}} \]
\end{document}
Best Answer
Probably, the document is using package
physics. It redefines the symbol for a different purpose. The old meaning of\divis saved in\divisionsymbol: