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Re: Exactly one element in a RDFS class

From: Hugh Glaser <hugh@glasers.org>
Date: Mon, 17 Nov 2014 15:54:49 +0000
Cc: Phil Archer <phil@philarcher.org>, Pavel Klinov <pavel.klinov@uni-ulm.de>, Victor Porton <porton@narod.ru>, SW-forum Web <semantic-web@w3.org>
Message-Id: <F0A5BAFA-FAD1-4D02-B37C-AA874150A6B2@glasers.org>
To: "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
I’m not sure that Victor's question is being answered here.
He certainly doesn’t mention querying or anything; or saying what the element is at the same time.

I read it to mean that he simply wanted to be able to specify a constraint.

Sort of an equivalent of owl:cardinality, I guess.
Now, if I understood owl:Restriction enough to put anything here publicly I might have a go at it, but… :-)

Could be.
Cheers

> On 17 Nov 2014, at 14:55, Peter F. Patel-Schneider <pfpschneider@gmail.com> wrote:
> 
> I'm having a very hard time coming up with any overlap between this discussion and anything that might happen in the RDF data shapes working group.  The working group is about detecting explicit information in RDF documents---this discussion is about how to create singleton classes, and maybe how to detect such singleton classes in an RDF encoding.
> 
> That said, SPARQL is used in several of the technologies being investigated by the working group and it is probably possible to write a SPARQL query to detect a singleton class in the RDF encoding of OWL, but this doesn't provide any true commonality.
> 
> peter
> 
> 
> On 11/17/2014 01:50 AM, Phil Archer wrote:
>> This sort of debate is exactly the kind of thing that is behind the newly
>> formed RDF Data Shapes working group. Its charter includes pointers to a bunch
>> of existing work in this area that may be useful.
>> 
>> See http://www.w3.org/2014/data-shapes/
>> 
>> Cheers
>> 
>> Phil.
>> 
>> 
>> On 16/11/2014 23:03, Pavel Klinov wrote:
>>> There's no simpler encoding. Nominals is the only feature in OWL 2
>>> which lets you say that a class has a single instance. And it has a
>>> unique serialization in RDF.
>>> 
>>> I don't think querying for this particular syntactic construct is complex.
>>> 
>>> However, writing RDF queries for OWL ontologies serialized in RDF (be
>>> that SPARQL or other RDF graph matching language) is usually not a
>>> great idea. You'll often have to deal with specifics of the RDF
>>> serialization which is complex for many OWL constructs (see [1])
>>> 
>>> Cheers,
>>> Pavel
>>> 
>>> [1] http://www.w3.org/TR/owl2-mapping-to-rdf/
>>> 
>>> On Sun, Nov 16, 2014 at 11:35 PM, Victor Porton <porton@narod.ru> wrote:
>>>> Your solution has the same problem as Patrick Logan's one. (See my previous
>>>> email.) In fact your solution is the same as Patrick Logan's one.
>>>> 
>>>> 17.11.2014, 00:28, "Pavel Klinov" <pavel.klinov@uni-ulm.de>:
>>>>> Sorry, my previous email got sent too soon.
>>>>> 
>>>>> Here's the link to the right place in the OWL 2 spec:
>>>>> 
>>>>> http://www.w3.org/TR/owl2-syntax/#Enumeration_of_Individuals
>>>>> 
>>>>> Cheers,
>>>>> Pavel
>>>>> 
>>>>> On Sun, Nov 16, 2014 at 10:52 PM, Victor Porton <porton@narod.ru> wrote:
>>>>>>  Is there any advise on how to code in RDFS or OWL the following statement?
>>>>>> 
>>>>>>  "The class X has exactly one element."
>>>>>> 
>>>>>>  --
>>>>>>  Victor Porton - http://portonvictor.org
>>>> 
>>>> --
>>>> Victor Porton - http://portonvictor.org
>>> 
>>> 
>> 
> 

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Received on Monday, 17 November 2014 15:55:15 UTC

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