- From: Bernard Vatant <bernard.vatant@mondeca.com>
- Date: Mon, 08 Jan 2007 15:24:21 +0100
- To: Dave Reynolds <der@hplb.hpl.hp.com>
- Cc: Semantic Web <semantic-web@w3.org>, Tim Berners-Lee <timbl@w3.org>
Hi Dave Thanks a lot for those clarifications. More below on tools behaviour. Dave Reynolds a écrit : > Does SWOOP warn you that this file is OWL/full and so can't be edited > safely? Nope. >> Loading and saving in Protégé 3.2 yields back >> >> <owl:AnnotationProperty >> rdf:about="http://www.example.org/ontology#altName"> >> <rdfs:subPropertyOf >> rdf:resource="http://www.w3.org/2000/01/rdf-schema#label"/> >> <rdf:type >> rdf:resource="http://www.w3.org/2002/07/owl#DatatypeProperty"/> >> </owl:AnnotationProperty> >> >> The DatatypeProperty class is added > > In OWL/DL AnnotationProperty and DatatypeProperty are disjoint, so > even though you are already in OWL/full this seems like a strange way > to be behave. Indeed, more than strange, this is a built-in bug IMO, that has been there in various Protégé releases for quite a while. Using GUI as well you can't create a simple annotation property. >> Now if I don't want to presume the property type and just declare >> >> <rdf:Property rdf:about="http://www.example.org/ontology#altName"> >> <rdfs:subPropertyOf >> rdf:resource="http://www.w3.org/2000/01/rdf-schema#label"/> >> </rdf:Property> >> >> SWOOP just ignores this declaration altogether, and the property is >> killed when saving. > > This is OWL/full, again does SWOOP warn you it might loose OWL/full-isms? Nothing of the like. SWOOP just seem to *ignore* this declaration. BTW I just found another strange behaviour of SWOOP. If you declare, using the GUI, a property as subproperty of rdfs:label, you have rdfs:label itself typed as owl:DatatypeProperty. There is definitely something broken here ... >> Protégé does not show the property in the GUI, but Jena saves it in >> the original form. > > Yes, Jena can happily read/write OWL/full files and certainly won't > loose triples like that. Indeed, but as long as you don't see them in the GUI, you think something is broken, and don't figure what until you look at the code. >> Well, all that is *very messy* indeed. Looks like that the semantics >> of annotation subproperties is defined nowhere, and randomly >> implemented in tools. > > Well in a sense the point of Annotation properties is that they don't > really carry any semantics, that's why they can be safely used in DL. I understand that. So according to you, declaration of annotation subproperties cannot bear any semantics. So would you recommend to avoid such declarations altogether? And in this case, what do I do about Tim's request for such declarations to be present in order to make Tabulator happy? >> a:myProperty1 rdfs:subPropertyOf b:yourProperty2 >> b:yourProperty2 rdf:type ex:SomePropertyType >> >> Does the above entails in RDFS >> >> a:myProperty1 rdf:type ex:SomePropertyType >> >> ?? (I guess yes, but maybe I'm wrong) > > No. For example, instead of ex:SomePropertyType consider > owl:TransitiveProperty then there is no reason why a subProperty of a > transitive property should itself be transitive. OK I see an example ex:ancestorOf rdf:type owl:TransitiveProperty ex:fatherOf rdfs:subPropertyOf ex:ancestorOf and ex:fatherOf is not a transitive property. So there is no formal opposition (in OWL-Full) to have a owl:DatatypeProperty being a subproperty of rdfs:label, even in an ontology where annotation, datatype and object properties are disjoint. Well I guess I am not the only one to get this wrong, if I judge by the way RDF tools handle this. Are such examples documented somewhere? Bernard -- *Bernard Vatant *Knowledge Engineering ---------------------------------------------------- *Mondeca** *3, cité Nollez 75018 Paris France Web: www.mondeca.com <http://www.mondeca.com> ---------------------------------------------------- Tel: +33 (0) 871 488 459 Mail: bernard.vatant@mondeca.com <mailto:bernard.vatant@mondeca.com> Blog: Leçons de Choses <http://mondeca.wordpress.com/>
Received on Monday, 8 January 2007 14:24:42 UTC