W3C home > Mailing lists > Public > semantic-web@w3.org > July 2012

Re: OWL equivalentClass question

From: Nathan <nathan@webr3.org>
Date: Fri, 13 Jul 2012 15:24:58 +0100
Message-ID: <50002FBA.7020309@webr3.org>
To: Michael Schneider <schneid@fzi.de>
CC: semantic-web@w3.org
Thanks Michael!

Much appreciated and thanks for the fast clear response. One other 
question whilst I'm here if you don't mind:

Under [1] (Owl Syntax 7.4 Enumeration of Literals) the example has:

   Functional-Style Syntax:
     DataOneOf( "Peter" "1"^^xsd:integer )
   RDF:
     _:x rdf:type rdfs:Datatype .
     _:x owl:oneOf ( "Peter" "1"^^xsd:integer ) .

note: *owl:oneOf*

However, under [2] (3.2.4 Parsing of Expressions - Table 12) it clearly 
shows:

   _:x rdf:type rdfs:Datatype .
   _:x owl:datatypeComplementOf y .

So which is it, owl:oneOf or owl:datatypeComplementOf ?

Many thanks as always,

Nathan

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


Michael Schneider wrote:
> [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
>>>
>>
> 
Received on Friday, 13 July 2012 14:25:57 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 1 March 2016 07:42:35 UTC