"Top level" packages ?

[Renaud Guérin <Renaud.Guerin@alcove.fr>]

Hello,

I'd like to determine, given a set of installed packages, the minimum
subset which implies all the others via dependencies. (So I can later
feed apt with a
smaller list which recreates the whole set on an another machine)
I'm looking at the Perl modules in pkg-order to help me in that task,
but being a beginner in both Perl and the Debian packaging system, I
find the use of these modules not very straightforward.

Has anyone done this before, and are the libraries in pkg-order the
right tool for the job ?

Thanks.