- From: Stasinos Konstantopoulos <konstant@iit.demokritos.gr>
- Date: Wed, 23 Apr 2008 14:10:32 +0300
- To: Phil Archer <parcher@icra.org>
- Cc: Public POWDER <public-powderwg@w3.org>
On Wed Apr 23 11:58:17 2008 Phil Archer said: > OK, thanks very much Stasinos, that's hugely helpful. I've worked (and > re-worked) through your comments on all this and would like to propose > the following which, I hope, is in line with what you have said and, no > less important, can be encoded in the XSLT that Kev is working on right > now. > > I've prepared several examples of POWDER descriptor sets and their > equivalent DR-S versions. Logically they begin with a simple one and end > up hideously complex just to prove that the same rules can be applied > and yield a consistent answer. > > So, the simple one first: [snipped lots of easy calls] > If the value of a property is a class then we have this situation: > > <descriptorset> > <ex:property1>value</ex:property1> > <ex:property2 > rdf:resource="http://example.org/semantic/powder.rdf#d1" /> > </descriptorset> But that was the whole point: the value of a property *cannot* be a class, it *has* to be in an instance. > Which generates: > > <owl:Class rdf:nodeID="descriptorset_1"> > <owl:intersectionOf rdf:parseType="Collection"> > <owl:Restriction> > <owl:onProperty rdf:resource="&ex;property1" /> > <owl:hasValue>value</owl:hasValue> > </owl:Restriction> > <owl:Restriction> > <owl:onProperty rdf:resource="&ex;property2" /> > <owl:hasValue > rdf:resource="http://example.org/semantic/powder.rdf#d1" /> > </owl:Restriction> > </owl:IntersectionOf> > </owl:Class> So, if "http://example.org/semantic/powder.rdf#d1" is of type "owl:Class", then this fragment is *not* OWL. seeAlso http://www.w3.org/TR/owl-ref/#hasValue-def: The value constraint owl:hasValue is a built-in OWL property that links a restriction class to a value V, which can be either an individual or a data value. [snipped lots of stuff invalidated by the previous statement] s
Received on Wednesday, 23 April 2008 11:11:33 UTC