Hi Andy, thanks for your answer, and I’m ok for the graph being a set of triples, it is the (very good) reason explaining why only one triple is produced. But the reasoner is not in forward model. It is a forward-RETE model, which means that the forward rules have to work incrementally, allowing to add and remove triples and maintaining the consistency of the model.
So in the case described by Sébastien, the forward-RETE model should not remove the inferred triple since another rule has its body terms still validated. At least, this last rule should have been fired in order to indicate it that the triple which was not created previously (because it was still in the graph) is going to be removed, so this last rule should produce it again. Chris. Christophe FAGOT, PhD RESPONSABLE R&D INFORMATIQUE intactile DESIGN Création d’interfaces + subtiles +33 (0)4 67 52 88 61 +33 (0)9 50 12 05 66 20 rue du carré du roi 34000 MONTPELLIER France www.intactile.com <http://intactile.com/> Hugh MacLeod : "It's not what the software does, it's what the user does" Les informations contenues dans cet email et ses documents attachés sont confidentielles. Elles sont exclusivement adressées aux destinataires explicitement désignés ci-dessus et ne peuvent être divulguées sans consentement de son auteur. Si vous n'êtes pas le destinataire de cet email vous ne devez pas employer, révéler, distribuer, copier, imprimer ou transmettre le contenu de cet email et devez le détruire immédiatement. > Le 28 janv. 2015 à 12:17, Andy Seaborne <[email protected]> a écrit : > > (Dave is not around at the moment so I'll try to answer some parts of your > question ...) > > On 28/01/15 10:28, "Sébastien Boulet [intactile DESIGN]" wrote: >> Hello, >> >> I have two rules which could produce the same triple: >> >> String rules = "[r1: (?a eg:p ?b) -> (?a, eg:q, ?b)]" + >> "[r2: (?a eg:r ?b) -> (?a, eg:q, ?b)]"; >> >> i have configured a GenericRuleReasoner in FORWARD_RETE mode. >> >> GenericRuleReasoner reasoner = new >> GenericRuleReasoner(Rule.parseRules(rules)); >> reasoner.setMode(GenericRuleReasoner.FORWARD_RETE); >> InfModel model = ModelFactory.createInfModel(reasoner, >> ModelFactory.createDefaultModel()); >> >> When a triple satisfy the first rule and another triple satisfy the second >> rule: >> >> Resource subject = model.createResource(); >> Property predicateP = model.getProperty("urn:x-hp:eg/p"); >> Literal literalA = model.createTypedLiteral("A"); >> Property predicateR = model.getProperty("urn:x-hp:eg/r"); >> >> model.add(subject, predicateP, literalA); >> model.add(subject, predicateR, literalA); >> >> only one triple is deduced: > > An RDF graph is a set of triples. > > A set only has one of each thing in it. > > If you > add(triple) > add(triple) > > you will see only one triple in the output. This is not to do with > inference, it is to do with an RDF graph being a set. > >> >> <rdf:RDF >> xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"; >> xmlns:j.0="urn:x-hp:eg/" > >> <rdf:Description rdf:nodeID="A0"> >> <j.0:r rdf:datatype="http://www.w3.org/2001/XMLSchema#string";>A</j.0:r> >> <j.0:p rdf:datatype="http://www.w3.org/2001/XMLSchema#string";>A</j.0:p> >> <j.0:q rdf:datatype="http://www.w3.org/2001/XMLSchema#string";>A</j.0:q> >> </rdf:Description> >> </rdf:RDF> >> >> When i remove the fist triple: >> >> model.remove(subject, predicateP, literalA); >> >> the sole deduced triple is removed even if the second rule is still >> satisfied: > > You ran the reasoner in forward model - it included all deductions at the > start and then does not run again until you ask it to. > > To trigger it again: > > InfModel.rebind() > "Cause the inference model to reconsult the underlying data to take into > account changes." > > or run in backward mode. > > Andy > >> >> <rdf:RDF >> xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"; >> xmlns:j.0="urn:x-hp:eg/" > >> <rdf:Description rdf:nodeID="A0"> >> <j.0:r rdf:datatype="http://www.w3.org/2001/XMLSchema#string";>A</j.0:r> >> </rdf:Description> >> </rdf:RDF> >> >> is it the expected behavior ? >> is there a workaround to deduce twice the same triple or at least to don’t >> remove the sole deduction ? >> >> Thanks >> >> >> Sébastien BOULET >> LEAD DÉVELOPPEUR >> >> intactile DESIGN >> Création d’interfaces + subtiles >> 04 67 52 88 61 >> 09 50 12 05 66 >> 20 rue du carré du roi >> 34000 MONTPELLIER >> France >> www.intactile.com <http://intactile.com/> >> >> Les informations contenues dans cet email et ses documents attachés sont >> confidentielles. Elles sont exclusivement adressées aux destinataires >> explicitement désignés ci-dessus et ne peuvent être divulguées sans >> consentement de son auteur. Si vous n'êtes pas le destinataire de cet email >> vous ne devez pas employer, révéler, distribuer, copier, imprimer ou >> transmettre le contenu de cet email et devez le détruire immédiatement.
