W3C home > Mailing lists > Public > www-rdf-logic@w3.org > April 2004

Re: Does Euler support owl:hasValue ?

From: Benjamin Nowack <bnowack@appmosphere.com>
Date: Wed, 14 Apr 2004 12:01:31 +0200
To: Seth Ladd <seth@picklematrix.net>
Cc: www-rdf-logic@w3.org
Message-ID: <PM-EH.20040414120131.1DEBE.1.1D@192.168.27.2>

On 14.04.2004 07:52:17, Seth Ladd wrote:
>
>Hello,
>
>Forgive me if this isn't the right place to ask Euler questions, but I 
>haven't been able to find a mailing list or contact for Euler.  If there 
>is a better place, please let me know.
>
>I am trying to write some tests using owl:hasValue and run it through 
>Euler.  Unfornately, I'm not having much luck.  I am trying say "any 
>object that has a property "dc:subject" and a value of "foo" is an 
>instance of a :Foo class".  I do it with:
>
>:Foo a owl:Class ;
>     rdfs:subClassOf [ a owl:Restriction ;
>                       owl:onProperty dc:subject ;
>                       owl:hasValue^^xsd:string "foo" ] .
>
>I then give it the facts:
>
>:foo a owl:Thing ; dc:subject^^xsd:string "foo" .
>dc:subject a owl:DatatypeProperty ; rdfs:range xsd:string .
>
>Then I ask:
>
>_:X a :Foo .
>
>But I don't get any proofs.  Of course, I could be asking the question 
>incorrectly.  Before I go down that route, I want to see if anyone knows 
>if Euler can handle the above owl:hasValue usage.

hi seth,
your class description above says that any instance of Foo will
have at least one dc:subject value "foo". that's the other way round
and not what you intended, I guess (i.e. there still can be non-Foo 
individuals with a dc:subject of "foo"). Euler could (if owl stuff is
supported) infer class membership if Foo was described as a complete
class via an owl:equivalentClass construct:

<owl:Class rdf:ID="Foo">
   <owl:equivalentClass>
      <owl:Restriction>
         <owl:onProperty rdf:resource="&dc;subject"/>
         <owl:hasValue rdf:datatype="&xsd;string">foo</owl:hasValue>
      </owl:Restriction>
   </owl:equivalentClass>
</owl:Class>


>
>Thanks for your tips or ideas!
>Seth

hope that helps.

best,
benjamin

--
Benjamin Nowack

Kruppstr. 82-100
45145 Essen, Germany
Received on Wednesday, 14 April 2004 07:45:13 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:52:48 GMT