"George Sakkis" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > "Christian Stapfer" <[EMAIL PROTECTED]> wrote: > >> <[EMAIL PROTECTED]> wrote: >> > try to use set. >> >> Sorting the two lists and then extracting >> A-B, B-A, A|B, A & B and A ^ B in one single >> pass seems to me very likely to be much faster >> for large lists. > > Why don't you implement it, test it and time it > to be more convincing about your intuition ?
The problem is in the generation of the test data. Even merely generating a set of (suitably "average", "random", and suitably "worst case") datasets might turn out to be a major undertaking. If the documentation stated the order-of-magnitude behavior of those basic operations up front, then I (and *anyone* else who ever wanted to use those operations on large lists / large sets) could do a quick order-of-magnitude estimation of how a certain program design will behave, performance wise. *Experimenting* is not necessarily as easy to do as you seem to believe. How do you, for example, hit upon the worst-case behavior with your test data? - Without knowing *anything* about the implementation it might a matter sheer luck. If you *know* something about the implementation then, of course, you might be able to figure it out. (But note that if you know *that* much about the implementation, you usually have an order-of- magnitude estimate anyway and don't need to do *any* experimenting in order to answer my question.) Regards, Christian -- http://mail.python.org/mailman/listinfo/python-list
