- From: Jeff Z. Pan <pan@cs.man.ac.uk>
- Date: Fri, 21 May 2004 23:42:39 +0100
- To: "Dan Brickley" <danbri@w3.org>, "Benjamin Nowack" <bnowack@appmosphere.com>
- Cc: <www-rdf-logic@w3.org>
On May 18, 2004 11:40 AM, Benjamin Nowack wrote: > >On 17.05.2004 19:41:26, Dan Brickley wrote: >> >><owl:Restriction> > <owl:onProperty rdf:resource="#hasParent" /> > <owl:hasValue rdf:resource="#Clinton" /> ></owl:Restriction> > >><owl:Restriction> > <owl:onProperty rdf:resource="#hasParentName" /> > <owl:hasValue>Bill Clinton</owl:hasValue> ></owl:Restriction> > >seems fine to me. you may add datatype information for a more precise description, Indeed. >although it may be sufficient to have it in the property and range definition, e.g.: ><owl:Restriction> <owl:onProperty rdf:resource="#hasParentName" /> <owl:hasValue rdf:datatype="&xsd;string">Bill Clinton</owl:hasValue> </owl:Restriction> >and/or ><owl:DatatypeProperty rdf:ID="hasParentName"> <rdfs:domain rdf:resource="#Person"/> <rdfs:range rdf:resource="&xsd;string"/> </owl:DatatypeProperty> >a related NOTE in the ref doc says [[ for datatypes "semantically equal" means that the lexical representation of the literals maps to the same value ]] I would suggest a quick check of the Semantics and Abstract Syntax document, whenever something formally and explicitly defined is needed. >I don't know, if something like >"1.0"^^xsd:float is "semantically equal" to "1.0"^^xsd:string No. As "1.0"^^xsd:float is mapped to a float while "1.0"^^xsd:string is mapped to a string. >or, in the example above, if >"Bill Clinton"^^rdfs:Literal is "semantically equal" to "Bill Clinton"^^xsd:string. In this case yes, because plain literals are treated as strings. >I assume it is. No, see above. >hm, and what about >"1.0"^^xsd:float vs. "1"^^xsd:integer? In general, it depends on the definitions of the value spaces of datatypes. In the above example, you should/can check the XML Schema type system. >I guess, property values have to be validated/adjusted against the intended range datatype before a hasValue restriction can be checked.. I don't think this is necessary. The datatype constraints from range axioms and from typed literals are independent from each other. Jeff -- Jeff Z. Pan ( http://DL-Web.man.ac.uk/ ) Computer Science Dept., The University of Manchester >now I'm left puzzled as well.. ;) benjamin -- Benjamin Nowack Kruppstr. 100 45145 Essen, Germany >thanks for any advice, > >Dan >
Received on Friday, 21 May 2004 18:35:41 UTC