- From: Danny Ayers <danny666@virgilio.it>
- Date: Fri, 10 May 2002 10:49:29 +0200
- To: "jan grant \(by way of \"Ralph R. Swick\" <swick@w3.org>\)" <cmjg@tribble.ilrt.bris.ac.uk>, <www-rdf-comments@w3.org>
>[on the text:] > >A parser is considered to pass the test if it produces a graph >isomorphic with the graph described by the N-triples output document. > >> > This is wrong, according to the standard definition of graph >isomorphism >> > (care when using words without accurate definitions...!). > >An RDF graph is a labelled digraph with (some) blank nodes - that is, >N-Triples "labels" on blank nodes are only artifacts of a graph >serialisation >mechanism. I'd always used terms like "isomorphism" to refer to the >appropriate equivalence relationship for the class of mathematical objects >I'm talking about at the time. I personally wouldn't have a problem with the original wording, but now it's been mentioned I suppose it has to be tied down. It's not entirely straightforward - ok, the labels we see might just be artifacts, but does a bNode carry more meaning than that suggested by the topology? My guess would be that it does (even if this will be the same for all bNodes), and so should be considered labelled. Would the following replacement >text suffice? > >A parser is considered to pass the test if it produces an RDF graph >(that is, a partially-labelled labelled digraph) isomorphic with the RDF >graph described by the N-triples output document. I'd be tempted to drop 'partially labelled'. Counting angels before breakfast, Danny.
Received on Friday, 10 May 2002 04:59:19 UTC