Re: disjointness of numerics

On 28 Jan 2009, at 15:58, Ian Horrocks wrote:

> The semantics of OWL 1 says that values of unsupported datatypes
> are interpreted as some element of a set that is at least as large  
> as the union of the interpretations of all the known datatypes and  
> is disjoint from the abstract domain. A reasoner implementing  
> Vanilla OWL would therefore not find this entailment, but nor would  
> it conclude that the two values are necessarily different.

This is true, but isn't the question "What would a reasoner  
supporting the built-in (but optional) datatypes float and integer do?"

Many (Cerebra, KAON2 I think) did not treat them as disjoint. Pellet,  
afacr, did. Arguably the (weakly) speced semantics defers to the XML  
Schema doc which says that they are.

Cheers,
Bijan.

Received on Wednesday, 28 January 2009 16:07:42 UTC