- From: Seth Russell <seth@robustai.net>
- Date: Thu, 14 Feb 2002 11:57:57 -0800
- To: <tarod@softhome.net>
- Cc: <www-rdf-logic@w3.org>, <www-rdf-comments@w3.org>, <www-rdf-interest@w3.org>
From: <tarod@softhome.net> > Seth Russell writes: > > > From: <tarod@softhome.net> > > > > > > re: http://robustai.net/mentography/rdfs_domain_range2.gif > > > > > > > > > Good try but I must say that it's not 100% what I asked for because > > for > > > > > the range issue you use > > > > > Class C > > > > > A is subClassOf C > > > > > B is subClassOf C > > > > > And then c range is C. It's a good aproach but it's not logically > > > > > correct, you are saying that range of c is (C or A or B) and I asked > > for > > > > > range of c should be (A or B) > > > > > > > > Ok, I saw this problem after I published the graph. I would need a way > > to > > > > say that there is no instances of C which is not and instance of A or B. > > > > I'm beginning to agree with Sean, there is no way to say this with the > > > > primitives of rdfs only. > > > It was posible before some RDFCore changes :) > > > > > > > What is your objection to using the daml schema? > > > > > > I have no objection, this is just a challenge. > > > > > > > > Now try it with the old aproach it's easier. > > > > > > > > What approach are you talking about here? > > > > > > Before some changes in the schema, that a property had two domains (at > > > the begining a property must only have one range, now it can have more > > than > > > one) means that the subject of the property must be in one of those > > > domains, it was a disjuntion of restrictions. When they added more than > > one > > > range if they had used this vision, the value of a property must be a > > > member of one of the domains, if that make sense to you, try it now. It's > > > very easy having this in mind. > > > > Well if the domain restraint is jisunctive and the range restraint is > > conjunctive, then I suppose your example would eaisly work that old way. > > But if one wanted the opposite case ( range (A and B). domain ( A or B)), > > then we still couldn't do it. Intiitively don't we want domain and range > > to be symmetric here? > > > > Mentograph available upon request. > > Seth Russell > > Sorry, I meant both of them should be disjuntive. Ok, I think I see what you meant. Is this it? http://robustai.net/mentography/rdfs_domain_range4.gif But then wouldn't that would break one of the basic concepts of RDF grpahs ... all triples are anded together ? Seth Russell
Received on Thursday, 14 February 2002 15:01:31 UTC