> I keep working around a little problem with unpacking in cases in which I > don't know how many elements I get. Consider this: > > def tabulate_lists (*arbitray_number_of_lists): > table = zip (arbitray_number_of_lists) > for record in table: > # etc ... > > This does not work, because the zip function also has an *arg parameter, > which expects an arbitrary length enumeration of arguments > which it would turn into a tuple (lists in this case). Now my function does > exactly the same thing ahead of zip. So, before I pass > the tuple "arbitrary_number_of_lists" to zip, I 'd need to unpack it but the > only way I know of is into variables: > > list1, list2, list3 = arbitrary_number_of_lists > zip (list1, list2, list3)
I don't get your problem here. This works for me: args = [range(5) for i in xrange(5)] print zip(*args) > With arbitrary number of lists it cannot be done this way. > > Question: Is there an unpacking mechanism for cases in which I don't > know--and don't need to know--how many elements I get, or an > argument passing mechanism that is the inverse of the tuplifier (*args)? No. It looks a little bit as if you aren't aware of the symetry behind the * and **-argument-passing schemes. I suggest reading up on them. Diez -- http://mail.python.org/mailman/listinfo/python-list
