Re: RIF and QL

From: jos.deroo@agfa.com
Subject: Re: RIF and QL
Date: Fri, 27 Jan 2006 13:57:01 +0100

> Hi, Enrico
> 
> [...]
> > Take, for example, the case in <http://www.w3.org/2005/rules/wg/wiki/ 
> > Managing_incomplete_information#disjunctive-info>, which I rephrase 
> > below.
> >
> > Given a KB with the only axiom:
> >
> >    kb:customer rdfs:subClassOf unionOf(kb:paysCash kb:paysCC).
> >
> > and the fact:
> >
> >    kb:customer("Paul").
> >
> > and the rules:
> >
> >    cons:paying-customer(X) :- kb:customer(X), kb:paysCC(X).
> >    cons:paying-customer(X) :- kb:customer(X), kb:paysCash(X).
> >
> > we actually get, as expected, with either SWRL FOL semantics or 
> > Rosati's style LP semantics:
> >
> >    cons:paying-customer("Paul").
> >
> > But with the local evaluation of each body I don't get it.
> 
> 
> Well, maybe I'm sleeping, but when instead of your 2 rules (in N3)
> {?X a kb:customer. ?X a kb:paysCC} => {?X a cons:paying-customer}.
> {?X a kb:customer. ?X a kb:paysCash} => {?X a cons:paying-customer}.
> 
> I use a single rule
> {?X a ?C. ?C owl:unionOf (kb:paysCash kb:paysCC)} => {?X a 
> cons:paying-customer}.
> 
> then given the facts
> kb:customer rdfs:subClassOf [ owl:unionOf (kb:paysCash kb:paysCC)].
> :Paul a kb:customer.
> 
> and given the rules
> http://www.agfa.com/w3c/euler/rpo-rules.n3
> 
> I'm getting proof evidence (*) for
> :Paul a cons:paying-customer.
> 
> What am I missing??

Well, perhaps, that you changed the rule, which is stepping outside of the
permissable actions?

> Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/

peter