Thanks Dave, that looks like a good idea, I've played a little with one-line generators (? the things similar to list comprehensions), but I'm still wrapping my head around how to use them. Meanwhile I'm reorganizing my code because I now understand better how to use iterators (i.e. the combinations function), and I'm exploring using tuples where I can instead of lists... if I followed an earlier conversation properly, I think garbage collection might happen more immediately with immutables than mutables, and this program is crashing either Python or my entire computer every time I run it... I'm generating a LOT of combinations.
On Sun, Jan 12, 2014 at 9:33 AM, Dave Angel <da...@davea.name> wrote: > Keith Winston <keithw...@gmail.com> Wrote in message: >> I've got this line: >> >> for k in range(len(tcombo)): >> tcombo_ep.append(list(combinations(tcombo, k+1))) >> >> generating every possible length combination of tcombo. I then test >> them, and throw most of them away. I need to do this differently, it >> gets way too big (crashes my computer). >> > You should learn how to write and use a generator. Anytime you > find yourself creating a huge list, and only navigating it once, > consider writing a generator instead. A generator is any function > that has a yield in it. You can turn the loop above into a > one-level generator by > > def gen (tcombo): > for k in range (len (tcombo)) > yield list (combinations (tcombo, k+1)) > > And depending how you use the nested list, remove the call to list > () for some real serious space savings. > > (untested) > > > >> any help will be appreciated. I don't really understand lambda >> functions yet, but I can sort of imagine they might work here >> somehow... or not. >> > A lambda is seldom necessary or useful in simple programs. >> > > > -- > DaveA nr > > > > ----Android NewsGroup Reader---- > http://www.piaohong.tk/newsgroup > > _______________________________________________ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > https://mail.python.org/mailman/listinfo/tutor -- Keith _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
