# siunitx: "inter-unit-product" doesn't work as expected

I have an up-to-date MiKTeX 2.9 installation on Windows 10, and recently I came across a weird behavior of siunitx where inter-unit-product doesn't affect the output as shown below.

A couple of days ago, it was working but now it doesn't. So, what might be the reason?

P.S. The log file can be found here.

\documentclass{exam}
\usepackage{mathtools}
\usepackage{unicode-math}
\usepackage{siunitx}

\sisetup{
per-mode=symbol,
per-mode=repeated-symbol,
inter-unit-product = \ensuremath{{}\cdot{}}
}

\begin{document}
\end{document}

• You've stuck random stuff inside the unit: it will force literal mode ... Nov 4, 2019 at 21:52
• Just out of curiosity: Why do you surround \newton\m\s\per\radian with \left[ and \right]? Without those fences, the output of \SI is just fine.
– Mico
Nov 4, 2019 at 21:52
• Side comment: The unit should never be put in square brackets. Nov 4, 2019 at 21:52
• @Mico I am experimenting, and seemingly I messed it up.
– Diaa
Nov 4, 2019 at 21:57
• @Diaa No, because some people prefer not to use the unit macro.s You can forbid-literal-units if you wish Nov 4, 2019 at 21:58

If, for some unfathomable reason, you simply must encase scientific units in square brackets, you shouldn't do it as

\si{\left[\newton\m\s\per\radian\right]}


Instead, do it as follows (in math mode, naturally):

\left[\si{\newton\m\s\per\radian}\right]


That said, I would strongly recommend against encasing scientific units in square brackets.

• Not only you, but rather the BIPM. ;-) Nov 5, 2019 at 0:05
• May I know how to have control over the space surrounding the inter-product dot?
– Diaa
Dec 7, 2019 at 17:17
• @Diaa - "Control over the space" is a rather broad objective. The option inter-unit-product = \ensuremath{{}\cdot{}} makes LaTeX insert a thinspace on either side of of \cdot, while inter-unit-product = \ensuremath{{\cdot}} instructs LaTeX to insert no whitespace at all.
– Mico
Dec 7, 2019 at 17:45
• Thanks for the help. I rather found the space quite wide, which made me want to reduce it a bit without removing it at all.
– Diaa
Dec 7, 2019 at 19:20
• @dias - My mind-reading skills are, sadly, rubbish. As a result, if a person asks me something but isn't clear about the objective, chances are nil that I will guess that objective correctly. :-( To get LaTeX to insert half a thinspace around \cdot, give inter-unit-product = \ensuremath{\mkern1.5mu\cdot\mkern1.5mu} a try. (Can you guess that 1thinspace=3mu?)
– Mico
Dec 7, 2019 at 19:51