Clojurians Log v2
rdf
Anybody here have any experience using http://sparnatural.eu/ ? It looks like an amazing query builder for RDF triplestores.
One thing I noticed is that is is not accessible by keyboard at all, which unfortunately means I would be violating the accessibility directive should I choose to use it. Perhaps an exception can be made, but it really is a shame to build such an elaborate UI and never once consider keyboard users.
Thanks for sharing… looks like an interesting idea
Do any of you have an RDF training resource that you like? I need to get some of the junior folks on one of my teams a solid grounding (and can’t spare the time to create & give the training myself). I’m familiar with some of the usual suspects, but curious to see what others have found.
So I'm playing with owl property chain axioms, and I think maybe there's something I'm not getting. Among other things I have this definition:
:hasQuantity a owl:ObjectProperty ;
owl:propertyChainAxiom (:primaryFigureOf :quantifiedAs) ;
dc:description "X hasQuantity Y := X is the primary figure of a scan quantified as Y" ;
.> (igraph/query g (voc/prepend-prefix-declarations
"Select ?s ?o Where {?s natlex:primaryFigureOf/natlex:quantifiedAs ?o}"))
({:s :natlex/TestTrajector, :o :natlex/TestQuantity})> (igraph/query g (voc/prepend-prefix-declarations
"Select ?s ?o Where {?s natlex:hasQuantity ?o}"))
() 
I’m guessing that the : prefix in your owl is defined to the same namespace that natlex is defined to in your queries, right?
Yes.
On closer inspection of the Jena docs, I don't see property chains mentioned on the table here: https://jena.apache.org/documentation/inference/index.html
I haven’t used the Jena reasoner. But the way it’s written, it looks like it might be OWL, and not OWL 2
(Property chains are OWL 2)
Ah. Good point
Funny that Jena still doesn't support OWL2.
From memory, Jena supports multiple reasoning systems (rules and tableaux). Is that right? I know that Dave Reynolds did the rules based reasoner, but not much more than that. I would have a steep learning curve to look at a tableaux reasoner (I understand the theory, but never looked at an implementation), but updating the rules reasoner should be accessible. This is because OWL2 has a full set of rules for RL. The question is… do I try this myself, or do I convince someone else to do it instead 🙂
Yeah I'm really hoping I don't need to get that close to the metal. :-)