- From: pat hayes <phayes@ai.uwf.edu>
- Date: Thu, 5 Dec 2002 11:05:24 -0600
- To: Roland Schwaenzl <roland@mathematik.uni-osnabrueck.de>
- Cc: www-rdf-comments@w3.org
>Thanks for the explanations ... > > >In RDF Semantics there is Section 4.3 (informative) on datatype >entailments: rdfD1 and rdfD2 - > >What is supposed to happen for an input like > > >xsd:decimal rdf:type rdfs:Datatype >aaa ppp "120"^^xsd:decimal > >in view of http://www.w3.org/TR/xmlschema-2 Section 3.2.3 in >particular the "Note" and 3.2.3.1 ? > >How many triples are supposed to result from applying rdfD1 and >rdfD2 - in case the RDF processor understands xsd:decimal. The rules should not be thought of as computational rules. They are valid inference rules, but a processor is not obliged to use them as written in forward-inference mode. I will add a sentence to clarify this point. The direct answer to your question is that they would, or could, generate potentially infinitely many conclusions, formed by adding '.0' at the end and any number of leading zeros at the beginning, of the lexical string. Obviously it would be more practical to restrict the use of the rules to a mode where the number of conclusions generated were restricted. For example, it would be fine, in practice, to always use them so as to replace any lexical form representing a decimal by its canonical form with all irrelevant zeros suppressed. Whenever there is such a canonical lexical form, restricting the rules so as to generate only that canonical form will always find identities in at most two steps. As you probably know, dealing with equations when performing inferences is always somewhat computationally fraught, since true equations can often generate infinitely many correct but silly conclusions. These equations - which is what these rules are, in effect - are no exception. Pat Hayes -- --------------------------------------------------------------------- IHMC (850)434 8903 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32501 (850)291 0667 cell phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes s.pam@ai.uwf.edu for spam
Received on Thursday, 5 December 2002 12:05:35 UTC