Paul Winkler wrote: > On Tue, Mar 27, 2007 at 03:25:00PM -0400, Jim Washington wrote: > >> A factoradic index is representable as a long integer. Given that >> integer and the canonical list, you can regenerate the permutation >> represented by that integer. So, instead of caching the sorted list >> itself, you find and keep this integer, which is all the information >> needed to algorithmically re-obtain the sorted list. >> >> So, this would be slower than caching, but (I think) faster than re-sorting. >> > > Doesn't it mean you need the entire canonical list in memory? > > Yes, I think so, at least in the implementation/algorithm I am using. There may be other implementations that do not need this. Note, however, that the canonical list does not have to be complex objects. The canonical list is just a representation of the "unsorted" state. It can, for example, be a proxy list of iids, list indexes, or OOBTree keys. The algorithm does not care what it is reordering.
-Jim Washington _______________________________________________ Zope3-dev mailing list [email protected] Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
