Is there a way to make the siunitx
package output a unit with a single slash using per-mode=symbol
and fallback to per-mode=reciprocal
when there is more than one slash?
\documentclass{article}
\usepackage{siunitx}
\begin{document}
\SI{1}{\metre\per\second} % would output 1 m/s
\SI{1}{\ampere\per\metre\per\second} % would output 1 A m-1 s-1
\end{document}
\SI[per-mode=symbol]{1}{\meter\per\second}
... I don't know an automatic way :-)