- From: Pat Hayes <phayes@ihmc.us>
- Date: Fri, 23 Feb 2007 11:31:51 -0600
- To: Jim Hendler <hendler@cs.umd.edu>
- Cc: public-owl-dev@w3.org
>At 10:44 AM -0500 2/23/07, ewallace@cme.nist.gov wrote: >>Jim Hendler wrote: >> >>>Let me join Matthew in requesting this - note also that >>>"DisjointUnion" doesn't answer this need in all cases - often we want >>>to make things disjoint that either belong to many different classes >>>or that we have disjunction of classes without wanting to imply that >>>it is in some way complete. >>> -JH >> >>+1 on adding an AllDisjoint construct >>DisjointUnion supports a common pattern used in a number of modeling >>languages (including UML and EXPRESS), and no one from WebOnt would be >>surprised that I am in favor of including it in OWL 1.1. However, just >>as Jim points out, there are many cases where one wants to specify >>disjointness across a set of classes which don't make up a complete >>covering. Many new OWL users are surprised that classes aren't disjoint by >>default. Once they get over this, they start looking for constructs in >>the language like DisjointUnion and AllDisjoint. >> >>-Evan > > > >actually, I do have a little problem with disjointUnion - the >problem is that this would be the first OWL feature (I think) that >combines two definitions at the same time -- so if I say > >Class A == DisjointUnion (B,C,D) (with the obvious meaning, no >syntax implied) > >then I am asserting both the definition of Class A AND the fact that >B,C, and D are disjoint. From a human point of view, I wonder if it >isn't better to avoid the syntactic sugar and have this remain as >two assertions > >Class A= Union(B,C,D) >AllDisjoint(B,C,D) > >just seems to me that the clarity in the modeling would be clearer +1 Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 cell phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Friday, 23 February 2007 17:32:12 UTC