Stand-alone units with package siunitx

Question

To avoid writing down all the units and the associated powers, I wanted to start to use the siunitx package but I have a problem. In fact :

• The pressure is \SI{10}{\mega\pascal} = "The pressure is 10 MPa"
• The pressure is 10 \mega\pascal = "The pressure is 10"

In other words, I can't write the units without using \SI{expression}{units}, which is quite restrictive. Does someone have any idea to fix it ?

Thanks in advance.

Answer 1

You can load the package with option free-standing-units, then define

\DeclareSIUnit\megapascal{\mega\pascal}

to allow \megapascal in document scope. You might also want unit-optional-argument to allow \megapascal[10], or space-before-unit to allow 10\megapascal to work.

I recommend the standard interface in which units are an argument to \SI.

Answer 2

I think I found the answer:

\usepackage{siunitx}

\sisetup{decimalsymbol=comma,expproduct=.,seperr}

I don't know why it works, but it works! I took all the packages of a friend that could do it and removed it one after the other to figure out that the \sisetup command allows me to do what I wanted.

Answer 3

To only get the units, you can do:

\SI{}{\mega\pascal}

or (the more correct one):

\si{\mega\pascal}