Reading the paper, I noticed that my name "put" for assigning a value to a position is highly nonstandard. I have changed it to "set" for version 1.1 of Vec. Hopefully, changing so soon will avoid confusion... sorry. Luca On 7/19/07, Hugo Ferreira wrote: > > Hello, > > For those of you interested in functional array consider Sylvain Conchon > and Jean-Christophe Filliātre paper in [1]. The Union-Find (UF) uses > persistent arrays as its base data structure. I have made tests with the > UF using the code provided, an implementation of k-BUF data structure > (delayed backtracking) and altered version of the persistent array (fat > nodes + delayed backtracking). The tests I did show that this version of > persistent arrays is very efficient (especially for single threaded > backtracking). > > Maybe Luca could pit his implementation against that of the article and > report on how they fare? > > Regards, > Hugo Ferreira. > > [1] http://www.lri.fr/~filliatr/ftp/publis/puf-wml07.ps > > Loup Vaillant wrote: > > 2007/7/18, Luca de Alfaro : > >> Dear All, > >> > >> I would like to share with you an Ocaml implementation of extensible > >> arrays. > >> The implementation is functional, based on balanced trees (and on the > >> code > >> for Set and Map); I called the module Vec (for vector - I like > >> short names). You can find it at > >> http://www.dealfaro.com/home/vec.html > >> Module Vec provides, in log-time: > >> > >> Access and modification to arbitrary elements ( Vec.put n el v puts > >> element > >> el in position n of vector v, for instance). > >> Concatenation > >> Insertion and removal of elements from arbitrary positions > >> (auto-enlarging > >> and auto-shrinking the vector). > >> as well as: > >> > >> All kind of iterators and some visitor functions. > >> Efficient translation to/from lists and arrays. > >> An advantage of Vec over List, for very large data structures, is that > >> iterating over a Vec of size n requires always stack depth bounded by > >> log n: > >> with lists, non-tail-recursive functions can cause stack overflows. > >> > >> I have been using this data structure for some months, and it has been > >> very > >> handy in a large number of occasions. I hope it can be as useful to > you. > >> > >> I would appreciate all advice and feedback. Also, is there a > repository > >> where I should upload it? Do you think it is worth it? > >> > >> All the best, > >> > >> Luca > > > > Very interesting. I always felt uneasy about the presence of > > imperative arrays without a functional counterpart. I can't wait to > > try it. > > > > Looking at your array type definition, I assume that the timings you > > specified are worst-case? Is it possible to achieve better (but > > amortized) bounds? Do you think it would be worth the trouble? > > > > I didn't see in your specs the complexity of your iterators. Does > > these work in linear time, like those of the List and Array module? > > > > Regards, > > Loup > > > > _______________________________________________ > > Caml-list mailing list. Subscription management: > > http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list > > Archives: http://caml.inria.fr > > Beginner's list: http://groups.yahoo.com/group/ocaml_beginners > > Bug reports: http://caml.inria.fr/bin/caml-bugs > > > > _______________________________________________ > Caml-list mailing list. Subscription management: > http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list > Archives: http://caml.inria.fr > Beginner's list: http://groups.yahoo.com/group/ocaml_beginners > Bug reports: http://caml.inria.fr/bin/caml-bugs >