This looks really horrible when I typeset it in Plain TeX:
$$[\vec r]$$
\bye
The vector arrow bleeds into the bracket on the right, it's not pretty at all. Is there a standard fix for this sort of thing?
Things like $(\vec r)$ are a bit better because of the curve on the parens, but not by much.

\xvecmacro here might help: http://tex.stackexchange.com/questions/44017/dot-notation-for-derivative-of-a-vector/44071#44071 (There's an example of how a vector r looks.) – Todd Lehman May 08 '14 at 22:36