- From: Graham Klyne <GK@ninebynine.org>
- Date: Mon, 08 Mar 2004 16:59:11 +0000
- To: "Jeff Z. Pan" <pan@cs.man.ac.uk>, <www-rdf-logic@w3.org>
At 08:48 08/03/04 +0000, Jeff Z. Pan wrote: >Hi Graham, > > > One of the reasons I asked this question was that I have been trying >to > > combine some datatype-specific deductions (integer arithmetic) >expressed in > > a scheme [1] inspired by the Pan/Horrocks paper [2], with >collections > > (lists) of data which are antecedent facts for the desired composite >rule > > of deduction. I am finding that it is surprisingly awkward to use >the > > generalized restriction for this purpose, and think that I am >probably > > missing a trick here. > >I am not sure I get your point here. Could you give an example to show >why it is hard to use the generalised restriction please? Jeff, There are two examples in my previous message at: http://lists.w3.org/Archives/Public/www-rdf-logic/2004Feb/0045.html for which Jos has provided quite straightforward Euler solutions in: http://lists.w3.org/Archives/Public/www-rdf-logic/2004Feb/0046.html using a conventional rule form with special properties, ala CWM. These examples don't, of themselves, show why it's hard to use the generalised restriction. But they are examples for which I haven't figured out an easy way to use it. #g -- > >My own experiments suggest that I must combine the > > restriction with a more conventional (antecedent=>consequent) form >of rule. > > > > The (half-baked) idea I was considering as a way to deal with >inference > > over a collection was to introduce a primitive along the lines of a >'fold', > > as found in functional programming languages (which has been shown >to have > > some degree of universality for expressing recursive/repetitive >functions > > [3]), and combine that with non-iterative/non-recursive inference >patterns. > > > > #g > > -- > > > > [1] > > >http://www.ninebynine.org/RDFNotes/RDF-Datatype-inference.html#sec-choice-constraint-classes > > > > [2] Horrocks, I. and J. Pan, "Web Ontology Reasoning with Datatype >Groups", > > 2003. > > >http://www.cs.man.ac.uk/~horrocks/Publications/download/2003/PaHo03a.pdf > > > > [3] J. Functional Programming 1 (1): 1-000, January 1993 > > c fl 1993 Cambridge University Press 1 > > A tutorial on the universality and expressiveness of fold > > Graham Hutton University of Nottingham > > (also at http://www.cs.nott.ac.uk/~gmh/fold.pdf) > > > > [4] http://www.agfa.com/w3c/euler/ > > > > > > > > ------------ > > Graham Klyne > > For email: > > http://www.ninebynine.org/#Contact > > > > ------------ Graham Klyne For email: http://www.ninebynine.org/#Contact
Received on Monday, 8 March 2004 12:00:01 UTC