http://trac.sagemath.org/sage_trac/ticket/3021
If someone cares to make the variable handling more clever, I'd be
pleased to have it merged.
Nick
>
> I care, I have written div and curl routines for my multivariable calc
> classes before, but they were more hackish than yours. I will try to
> review that ticket soon, if no one beats me to it.
Unfo, it's definitely needs work -- it's just a sage script that shows
how one could do it.
Nick