Thanks. May be flatten should be build into the language somehow....
"Paul McGuire" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > "It's me" <[EMAIL PROTECTED]> wrote in message > news:[EMAIL PROTECTED] > > Okay, I give up. > > > > What's the best way to count number of items in a list? > > > > For instance, > > > > a=[[1,2,4],4,5,[2,3]] > > > > I want to know how many items are there in a (answer should be 7 - I don't > > want it to be 4) > > > <snip> > > I've sure seen a lot of questions about the flattening of lists. I found > this version of flatten somewhere, I thought I got it from the Python > Cookbook but I can't find it now. Perhaps it was posted here on c.l.py. I > *don't* claim authorship, I'm merely an admirer of such a clean-looking > solution. > > def flatten(a): > if not isinstance(a, (tuple,list)): return [a] > if len(a)==0: return [] > return flatten(a[0])+flatten(a[1:]) > > a = [[1, 2, 4], 4, 5, [2, 3], 6, [6], [], 'askjdf'] > > print len(flatten(a)) > > gives the value 10. > > Considering how often this comes up, might there be a place for some sort of > flatten() routine in the std dist, perhaps itertools? > > -- Paul > > -- http://mail.python.org/mailman/listinfo/python-list
