On Wed, Sep 23, 2015 at 12:29 PM, Wouter Beek <m...@wouterbeek.com> wrote:
> Hi Dimitris, > > Thanks a lot for the pointers so far and thanks for solving the > *dereference* issue! However, I am still not able to find a > specification of the *mappings* of the DBpedia datatypes. I will explain > a bit more about what this means since we seem to be talking about slightly > different things here. > > According to the RDF 1.1 specification > <http://www.w3.org/TR/rdf11-concepts/#section-Datatypes>: "A datatype > consists of a lexical space > <http://www.w3.org/TR/rdf11-concepts/#dfn-lexical-space>, a value space > <http://www.w3.org/TR/rdf11-concepts/#dfn-value-space> and a lexical-to-value > mapping > <http://www.w3.org/TR/rdf11-concepts/#dfn-lexical-to-value-mapping> > [...]" > > I am looking for these mappings for, e.g., datatype http://dbpedia > .org/datatype/inhabitantsPerSquareKilometre. My first attempt was to > dereference these IRIs and maybe find a specification of the mappings > there. Now that these IRIs can be dereferenced (thanks for fixing this!), > the dereference does not seem to contain (a links to) a specification of > these mappings. > > A concrete example of a datatype IRI that *does* provide these mappings > in accordance with the RDF 1.1 specification is `xsd:gMonthDay`. If you > dereference the following IRI you receive (a link to) a specification of > the mappings: http://www.w3.org/2001/XMLSchema#gMonthDay. These > mappings can be implemented by software in order to correctly interpret > 〈xsd:gMonthDay,"06-12"〉 which number denotes the month and which number > denotes the day. > > The mappings are important since, e.g., 〈`dbp:centimetre`,1.0〉 may be > defined as `xsd:float` and a 〈`dbp:usDollar`,1.0〉 may be defined as > `xsd:decimal` (and float 1.0 ≠ decimal 1.0). In other words, the way in > which the DBpedia datatypes are defined (preferably in terms of XSD) is > important in order to determine the meaning of literals in which DBpedia > datatypes appear. > > Hope this makes my initial question a bit clearer! > Hi Wooter, Yes it does but currently we do not have such definitions. The datatypes are exported automatically from code [1] and we currently support only the existing high level declaration only. If this is needed, we are open to suggestions or direct PRs I suggest you open up a new issue on this in the ontology tracker and continue the discussion there Cheers, Dimtiris [1] https://github.com/dbpedia/extraction-framework/blob/master/core/src/main/scala/org/dbpedia/extraction/ontology/OntologyDatatypes.scala > > --- > Cheers > , > Wouter. > > Email: m...@wouterbeek.com > WWW: wouterbeek.com > Tel: +31647674624 > -- Kontokostas Dimitris
------------------------------------------------------------------------------
_______________________________________________ Dbpedia-developers mailing list Dbpedia-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dbpedia-developers
