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Re: OWL equivalentClass question

From: Michael Schneider <schneid@fzi.de>
Date: Fri, 13 Jul 2012 15:05:56 +0200
Message-ID: <50001D34.8030408@fzi.de>
To: <semantic-web@w3.org>, <nathan@webr3.org>
[Hrmph, I found another error in my first post. So forget
all my previous posts, here is complete rewrite with the
errors being fixed.]

Hi Nathan!

In the context of datatypes and data ranges (including
datatype restrictions, as you use them in your examples),
the term "owl:equivalentClass" is used in the RDF syntax
of OWL 2 for stating /datatype definitions/; see [1] for
the specification of datatype definitions, and Table 16
in [2] for the reverse RDF mapping from the RDF encoding
of datatype definitions to their OWL 2 functional syntax
counterparts.

Further, from the last entry of Table 12 in [2], you can
see that the RDF encoding of /datatype restrictions/ is
only defined for blank nodes (as in your first example),
so the mapping of datatype definitions does not apply if
a URI is used instead (as in your second example).

Hence, only the first of your two examples is syntactically
valid in OWL 2 DL, and its meaning is, as you certainly
intended, to define a name (URI) for the given datatype
restriction.

[1]
<http://www.w3.org/TR/2009/REC-owl2-syntax-20091027/#Datatype_Definitions>
[2] <http://www.w3.org/TR/2009/REC-owl2-mapping-to-rdf-20091027/>

Best,
Michael

> Am 13.07.2012 14:17, schrieb Nathan:
>> Hi all,
>>
>> I'm looking to define a few Datatype's, and wondered why
>> owl:equivalentClass is used for all complex types in the
>> primer/documentation.
>>
>> For example what's the difference between:
>>
>> :personAge  owl:equivalentClass
>>    [ rdf:type  rdfs:Datatype;
>>      owl:onDatatype  xsd:integer;
>>      owl:withRestrictions (
>>       [ xsd:minInclusive  "0"^^xsd:integer ]
>>       [ xsd:maxInclusive  "150"^^xsd:integer ]
>>      )
>>    ] .
>>
>> and:
>>
>> :personAge rdf:type  rdfs:Datatype;
>>    owl:onDatatype  xsd:integer;
>>    owl:withRestrictions (
>>     [ xsd:minInclusive  "0"^^xsd:integer ]
>>     [ xsd:maxInclusive  "150"^^xsd:integer ]
>>    ) .
>>
>> Is the second example valid, any reasons not to do it, what am I missing
>> here?
>>
>> TIA,
>>
>> Nathan
>>
>

-- 
.........................................................
Dipl.-Inform. Michael Schneider
Research Scientist, IPE / WIM

FZI Forschungszentrum Informatik
Haid-und-Neu-Str. 10–14
76131 Karlsruhe, Germany
Tel.: +49 721 9654-726
Fax: +49 721 9654-727

michael.schneider@fzi.de
www.fzi.de

.........................................................
Forschungszentrum Informatik (FZI) an der Universität Karlsruhe
Stiftung des bürgerlichen Rechts
Stiftung Az: 14-0563.1 Regierungspräsidium Karlsruhe
Vorstand: Dipl. Wi.-Ing. Michael Flor, Prof. Dr. Ralf Reussner,
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Received on Friday, 13 July 2012 13:06:24 UTC

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