js wrote: > By eliminating list cloning, my function got much faster than before. > I really appreciate you, John. > > def prefixdel_recursively2(alist): > if len(alist) < 2: > return alist > > first = alist.pop(0) > unneeded = [no for no, line in enumerate(alist) if > line.startswith(first)] adjust=0 > for i in unneeded: > del alist[i+adjust] > adjust -= 1 > > return [first] + prefixdel_recursively(alist) > > > process stime > prefixdel_stupidly : 11.9247150421 > prefixdel_recursively : 14.6975700855 > prefixdel_recursively2 : 0.408113956451 > prefixdel_by_john : 7.60227012634
Those are suspicious results. Time it again with number=1, or a fresh copy of the data for every iteration. I also have my doubts whether sorting by length is a good idea. To take it to the extreme: what if your data file contains an empty line? Peter -- http://mail.python.org/mailman/listinfo/python-list
