On Apr 26, 2012, at 12:54 AM, Stefan Holdermans wrote: > Sjoerd, > > I am sorry, as I already wrote, I decided to deprecate the package.
That's too bad, I really love these kind of data structures. (That's why I keep ranting about it, sorry about that.) > >> [3] defines the union as h(u) = max(f(u), g(u)) where f, g and h are >> multiplicity functions. > > Which is the same, as [3] is about multisets, not signed multisets. Chapter 3 of [3] is about Hybrid Sets. > >> [...] and this is also what your implementation does. (Map.unionWith max >> does not do a max if the key is not in one of the maps, i.e. if one of the >> multiplicities is 0.) > > I am aware of that. Why are you explaining this? Because we can't seem to get to an agreement. Usually this is because of a misunderstanding, so I try be as clear as possible, so you can understand my position, or point out my mistake. > >> I think if your union would follow the definition with max as in [3] and [4] >> it is not confusing. But then empty would not be the identity of that union >> (that would be the signed multiset with multiplicity negative infinity for >> all elements), so it would still not be a good choice for the Monoid >> instance. > > Let's agree to disagree. This is not constructive and, moreover, going > nowhere. I'd prefer to keep arguing actually. ;-) But if you have something better to do, I won't bother you anymore. greetings, Sjoerd >>> [3] Apostolos Syropoulos: Mathematics of Multisets. WMP 2000: 347-358 _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
