Albert-Jan Roskam wrote: > I want to repeatedly search a list to test whether that list contains a > given element X. Of course, I can use membership testing using "in" > (list._contains__). But how is this method implemented? It seems to just > walk through the whole list from beginning to end (see timeit code below).
Indeed. > Is it faster to do a binary search on a sorted list, given that this task > has to be done repeatedly? Much faster. You don't see that in your timings because you include the creation of the range(10**7) list in your measurement. If you used a set instead of a list you could use "in", and it would be even faster than bisect. > Can such a program be scaled to lists that do > not fit into memory (maybe using shelve?)? That would slowdown things a lot. Disk access is *much* slower than RAM. _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
