- From: Bijan Parsia <bparsia@cs.man.ac.uk>
- Date: Tue, 21 Aug 2007 19:10:16 +0100
- To: Reto Bachmann-Gmür <reto@gmuer.ch>
- Cc: semantic-web@w3.org
On 21 Aug 2007, at 16:42, Reto Bachmann-Gmür wrote: > I'm writing an ontology with properties pointing to literals > representing the following: > - media types (eg: "application/xhtml+xml") > - media ranges (eg: "application/*") > - fully qualified java-class names (eg: "org.example.tools.MyTool") > > While I could use xsd:string I think it would be better to use custom > datatypes to have literals like > "org.example.tools.MyTool"^^http://example.org/datatypes#javaClass. > > My question: > - Anyone knows a place where such datatypes are already defined? Not me. > - Datatypes are typically defined in an XML-schema, is there an > ontology > to do so in RDF? RDF has pretty limited datatype support in general (both in the spec and in the tools...as far as I know). OWL has somewhat better support including required support for xsd:string and xsd:integer, plus at least defined support for other simple types: <http://www.w3.org/TR/2003/WD-owl-semantics-20030203/syntax.html#2> Deriving URIs for user defined datatypes was left unspecified in deference to the XML Schema working group. There's a discussion you might find interesting: <http://www.w3.org/TR/swbp-xsch-datatypes/> (Pellet implemented the daml solution.) OWL 1.1 has a built-in vocabulary for user defined datatypes: <http://www.webont.org/owl/1.1/owl_specification.html#4.3> The rdf form is at the top of: <http://www.webont.org/owl/1.1/rdf_mapping.html#2> > - Is it a good idea to define the datatypes in the same namespace > as the > ontology using them? I think it's a matter of taste. Cheers, Bijan.
Received on Tuesday, 21 August 2007 18:09:05 UTC