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Re: observation on owl:real

From: Dave Reynolds <der@hplb.hpl.hp.com>
Date: Fri, 17 Apr 2009 08:48:36 +0100
Message-ID: <49E83454.3000701@hplb.hpl.hp.com>
To: Axel Polleres <axel.polleres@deri.org>
CC: "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>
Dave Reynolds wrote:
> Axel Polleres wrote:
>> Since owl:real is disjoint from float and double, it appears that the 
>> lexical space for owl:real, i.e. those owl:real values lexically 
>> expressible in RIF, actually just conincides with that of xs:decimal.
>>
>> So, one could say the lexical space of owl:real is the same as the one 
>> for xs:decimal?
>>
>> Given that, I kind of fail to see the need for owl:real at all for our 
>> purposes... resp., I fail to see where it would NOT coincide with 
>> xs:decimal.
>>
>> Opinions?
> 
> This seems like a bug in the OWL specs.
> 
> I had assumed that owl:real would be redefined to be the union of float, 
> double and decimal (perhaps better named owl:number).
> 
> Since, as you say, they have actually defined it as disjoint with float 
> and double I agree it serves no purpose and should be dropped.
> 
> Dave

On more reflection ... for OWL the current definition is not meaningless 
because they have owl:rational and so owl:real includes those as well as 
xsd:decimal.  For us, not having owl:rational makes owl:real with the 
current definition fairly useless.

Dave
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Received on Friday, 17 April 2009 07:49:28 GMT

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