On 13/06/2006 6:28 PM, Paul McGuire wrote: > (Oh, and I like groupby too! Combine it with sort to quickly create > histograms.) > > # tally a histogram of a list of values from 1-10 > dataValueRange = range(1,11) > data = [random.choice(dataValueRange) for i in xrange(10000)] > > hist = [ (k,len(list(g))) for k,g in itertools.groupby(sorted(data)) ]
That len(list(g)) looks like it uses O(N) memory just to find out what N is :-( The best I could come up with is sum(itertools.imap(lambda x: 1, g)) -- but that does look a bit ugly ... -- http://mail.python.org/mailman/listinfo/python-list
