- From: Jeen Broekstra <jeen.broekstra@aidministrator.nl>
- Date: Fri, 20 Sep 2002 13:13:21 +0200
- To: m batsis <mbatsis@netsmart.gr>
- CC: www-rdf-interest@w3.org
m batsis wrote: > * Can someone please point to what a property range defaults to? It does not default to anything. If the range is unspecified, then that's it: no range. Same for domain. > * IF I am correct, when a property has multiple ranges, all of them > must be satisfied (does not make sence to me;-). Can someone please > explain the reasons behind this? There is an interesting discussion about this in the mailinglist archives (actually, there are several :)), that may shed some light on this. One possibly interesting thread starts at http://lists.w3.org/Archives/Public/www-rdf-interest/2000Sep/0132.html The issue can also be found the in the RDF issue list that the RDF Core WG maintains: http://www.w3.org/2000/03/rdf-tracking/#rdfs-domain-and-range > * How can I have two dissjoint ranges in the same property? You can't. Or actually you can, but then no instances can exist that use this property. By the way, most[1] inferencers over RDF Schema interpret the domain/range property semantics as inference rules rather than constraints, which basically means that whenever you introduce a property p with a certain range R (p rdfs:range R), and you introduce a instance a with that property (a p b), its value is automatically derived to be of type R (b rdf:type R). Regards, Jeen [1] for sufficiently low values of most, that is :) -- jeen.broekstra@aidministrator.nl aidministrator nederland bv - http://www.aidministrator.nl/ julianaplein 14b, 3817 cs amersfoort, the netherlands tel. +31-(0)33-4659987, fax. +31-(0)33-4659987
Received on Friday, 20 September 2002 07:14:17 UTC