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Re: OWL, XML-RDF and Imports

From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
Date: Mon, 17 Feb 2003 10:10:33 -0500 (EST)
Message-Id: <20030217.101033.132969493.pfps@research.bell-labs.com>
To: jjc@hplb.hpl.hp.com
Cc: seanb@cs.man.ac.uk, www-webont-wg@w3.org

From: "Jeremy Carroll" <jjc@hplb.hpl.hp.com>
Subject: RE: OWL, XML-RDF and Imports
Date: Mon, 17 Feb 2003 14:27:02 +0100

> 
> > > > > - my pet hate rule for DisjointClasses which can be split
> > > > > e.g.
> > > > > DisjointClasses(unionOf(<a>,<b>),<c>,<d>,unionOf(<e>,<f>))
> > > > > creates six owl:disjointWith triples between four nodes, two of
> > > > which are
> > > > > blank.
> > > > > If the five triples involving the blank nodes are all in one
> > > > file, with the
> > > > > sixth triple in a second file, then you have a point.
> > > >
> > > > I don't see a problem here, as this would then correspond to
> > a five-way
> > > > disjoint in one file and five disjoints in the other file.
> > >
> > > No, because the blank nodes cannot be shared between files.
> >
> > I don't think that this would be required.  Replicating the (unnamed)
> > description in both files would do the trick.
> >
> >
> 
> Semantically yes, syntactically no.

Why not?  It is, after all the translation of a semantically-equivalent bit
of syntax. 

> I think that points to a way forward with these rules
> 
> DisjointClasses(d1,...,dn)
> 
> is equivalent to n(n-1)/2 statements
> 
> DisjointClasses(di,dj)
> 
> and the pair statements are easier to deal with syntactically.

> To me the remaining problem is to how to do so without necessitating an
> explosion of repetition that might be necessary.

What explosion?  At worst it would be n^2.

> Jeremy

peter
Received on Monday, 17 February 2003 10:12:01 GMT

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