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Re: property cardinality

From: Andrei S. Lopatenko <andrei@derpi.tuwien.ac.at>
Date: Tue, 27 Nov 2001 21:50:11 +0100
Message-ID: <03b901c17785$1b6ba640$a6498280@tuwien.ac.at>
To: <Joachim.Peer@unisg.ch>
Cc: <www-rdf-logic@w3.org>
Dear Joachim
Both definitions are correct for your application
You can use only one of them, only the first or only the second
But really the second, I think, better
The first one says that for class Person there is possible only one "age".
If "age" is not defined as UniqueProperty, then another class withour such
restriction can have more thern one "age"
The second says that the "age" is unique property for any class. And it is
more correct in real world (I hope)
The cardinality one for "age" is a property of property "age", not of
specific class


Best regards
MSc Andrei S. Lopatenko
Researcher
Vienna University of Technology
Extension Centre
http://derpi.tuwien.ac.at/~andrei/




----- Original Message -----
From: <Joachim.Peer@unisg.ch>
To: <www-rdf-logic@w3.org>
Sent: Tuesday, November 27, 2001 9:07 PM
Subject: DAML: property cardinality


> hellol DAML researchers!
>
> my question is: how can i enforce that a property (lets say "age") of a
> Class (lets say "Person") occurs n time in an instanciation of that class?
>
> in other words, i would like to declare something like that:
>
> *) illegal:
> <Person/>
>
> *) illegal:
> <Person>
>   <age>72</age>
>   <age>73</age>
> </Person>
>
> *) legal:
> <Person>
>   <age>72</age>
> </Person>
>
>
> - - - from the examples i got the following possibility:
>
> ...
> <daml:Class rdf:ID="Person">
>   <rdfs:subClassOf>
>     <daml:Restriction daml:cardinality="1">
>       <daml:onProperty rdf:resource="age"/>
>     </daml:Restriction>
>   </rdfs:subClassOf>
> </daml:Class>
> ...
> <daml:DatatypeProperty rdf:ID="age">
>    <rdf:type rdf:resource
> ="http://www.daml.org/2001/03/daml+oil#UniqueProperty"/>
>    <rdfs:range
rdf:resource="http://www.w3.org/2000/10/XMLSchema#integer"/>
> </daml:DatatypeProperty>
> ...
>
>
> my question is:
> - is this correct?
> - is there a shortcut for that?
>
>
> thanks in advance,
> joachim
>
>
Received on Tuesday, 27 November 2001 15:42:48 UTC

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