I want to represent dBm in LaTeX. I have included the siunits package. But only dB is included. What is the best way to represent other units?
[Tex/LaTex] LaTeX package for units not included in siunits
units
Related Solutions
As the author of siunitx
I have some idea about the relative strengths of the various alternatives. There are various things that need to be done for units:
- Semantic input of units, so
\kilo\metre
rather thankm
: this allows special effects such as reformatting fractions 'on the go' (some people prefer to use literal input, and this ideally needs to be supported too). - Formatting of numbers, for example dividing up digits into groups.
- Correctly presenting awkward symbols such as the micro symbol.
- Setting the font: many guidelines call for units to be in upright roman font with no bold or italic variation.
- Keeping numbers and units together (no space breaking)
Many packages have been written to address one or other aspect of this question. For example, SIunits
is good at providing semantic input, whereas SIstyle
focusses on correct typesetting but leaves the input to the user. On the other hand, unitsdef
sticks to doing only units and does not worry about other aspects.
The aim of the siunitx
package is to cover all of the requirements above, and to provide a way that package behaviour can be altered. Thus it uses a series of key-value options that will change how the output is formatted. The options can be applied to the entire document or to an individual piece of input. It also is designed to work in either math or text mode equally well. I have also been very careful to provide up to date advice about the internationally-agreed units in the documentation of siunitx
.
As a demo, using the latest release of siunitx
the following all show off the package:
\documentclass{article}
\usepackage{siunitx}
\begin{document}
\begin{itemize}
\item \qty{100}{\degreeCelsius}
\item \qty{3e5}{\km\per\s} or \qty[per-mode = symbol]{3e5}{\km\per\s}
\item \unit{\newton\metre\squared\per\kilogram\squared} or
\unit[per-mode = symbol]{\newton\metre\squared\per\kilogram\squared}
\item \( \qty{10}{\kilo\hertz} = \qty{1}{\per\second\tothe{4}} \)
\item \qty[parse-numbers = false]{\sin(x)}{\metre}
\end{itemize}
\end{document}
There are a couple of notes to bear in mind if using siunitx
. First, it requires e-TeX, which can be an issue with some publishers (even over 10 years after it was finalised!). Secondly, the formatting does take up some time. There are settings to turn things off but it's always the case that working by hand will ultimately be faster. However, the upside of clearer and more flexible input is in my opinion worth it.
One other point is that siunitx
is under development, with bug fixes and new features (there is a list for v3.1). In contrast, both SIunits
and SIstyle
are depreciated: bug fixes only. The units
and unitsdef
packages have not been updated for many years.
Use the SIunits package. Note that SI units are to be typeset in roman type, not italics! And please don't mix information and units. “g C” (with a thin space) can mean only one thing, namely the product of the units gram and Coulomb. Mixing in information like C for carbon with the units is a cardinal sin. A major point of standardised units with a standardised notation is disambiguation – if you see an SI unit in a paper far from your own speciality you should still be able to understand what it means.
Please refer to the style guides at the NIST SI units home page for further details.
Best Answer
With
SIunits
:I would (not surprisingly) use
siunitx
. This looks like a separate unit for which I might useOn the other hand, if it's a qualifier then