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Comment on Formal Semantics: complementOf usage

From: Ivan Herman <ivan@w3.org>
Date: Mon, 14 Jul 2008 16:22:05 +0200
Message-ID: <487B610D.6000606@w3.org>
To: public-powderwg@w3.org
Comment on http://www.w3.org/TR/2008/WD-powder-formal-20080709/, Formal 
Semantics

Example 3.8, POWDER-S for complement with several classes...

The last example says:

<owl:Class>
   <owl:intersectionOf rdf:parseType="Collection">
     <owl:Class rdf:about="#iriset_3"/>
     <owl:Class>
       <owl:complementOf rdf:parseType="Collection">
         <owl:Class rdf:about="#iriset_2"/>
         <owl:Class rdf:about="#iriset_1"/>
       </owl:complementOf>
     </owl:Class>
   </owl:intersectionOf>
   <rdfs:subClassOf rdf:ID="#descriptorset_3"/>
</owl:Class>

However, http://www.w3.org/TR/owl-ref/#complementOf-def says:

[[[
An owl:complementOf property links a class to precisely one class 
description.
]]]

The example links complementOf to an rdf:List, and I am not sure that is 
fine. I would expect the slightly more complex

<owl:complementOf>
    <owl:Class>
       <owl:unionOf rdf:parseType="Collection">
         <owl:Class rdf:about="#iriset_2"/>
         <owl:Class rdf:about="#iriset_1"/>
	  </owl:unionOf>
    </owl:Class>
</owl:complementOf>

I also spotted a similar problem in Example 4.5. In this case the 
collection is not necessary at all (owl:Restriction is a Class).


Cheers

Ivan

-- 

Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
PGP Key: http://www.ivan-herman.net/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf

Received on Monday, 14 July 2008 14:32:29 GMT

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