[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Christopher added a comment. Coincidentally, it seems that there are people who know a lot more about this than I do that have debated this issue at length in a long and very informative thread: CRS specification (was: Re: ISA Core Location Vocabulary)

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Smalyshev added a comment. I think WKT literal should specify the coordinate system, otherwise it becomes essentially useless - you can not do any queries on in if the literal may mean something on Earth or something on the Moon. If you query "give me items in within 50-mile radius of Paris"

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Christopher added a comment. @Smalyshev so, by stating that geometry and CRS are different, you then concur with the main arguments referenced above that they should not be conflated in a simple literal. @Daniel I agree with the idea of specifying the CRS as an additional component of the G

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Smalyshev added a comment. > Finally, I do not feel that it is accurate to use a Wikidata entity (e.g. Mars) as a CRS It is not 100% accurate as that URL does not contain (currently) description of CRS but it is the best option we have. At least it does define which planetary body (and

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

daniel added a comment. @Christopher I don't see why we shouldn't use wikidata URIs as CRS identifiers. However, I agree that Q2 and Q111 are too unspecific to be used as a coordinate system. We would want to use something like Q11902211. This points out a problem in our use of the "re

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Christopher added a comment. Please see geoSPARQL CRS design is debatable from the W3C Coordinate Reference System website. Also, #7 here: the conflation of CRS with with the WKT in a literal has many undesir

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Smalyshev added a comment. I think those are two different things. The spec you are quoting is the description of coordinate systems in WKT. However, what we have is not description of the coordinate system, but description of a point in some coordinate system which we do not specify (and re

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Smalyshev added a comment. I'm not sure I understand what you mean. As you can see for yourself in http://schemas.opengis.net/geosparql/1.0/geosparql_vocab_all.rdf, there are literals that contain rich semantics - WKT, GML, etc. Those are serializations of complex objects, recorded in RDF as

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Christopher added a comment. Eh, http://schemas.opengis.net/geosparql/1.0/geosparql_vocab_all.rdf#wktLiteral is an RDFS Datatype so the semantics are defined by the RDF schema, right? But, I found this http://docs.opengeospatial.org/is/12-063r5/12-063r5.html that demonstrates that the WKS

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Smalyshev added a comment. Literal value is not an URI, that is correct, and that value is a literal value. However, literal value can have type-defined semantics, and that semantics can - and in the case of this value does - have internal components, one of which can be URI. This semantics

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Christopher added a comment. Thanks for the clarification. However, the Req 10 of the geoSPARQL specification seems to be at odds with the definition of a "literal value". (According to https://www.w3.org/TR/rdf11-concepts/#section-Graph-Literal). The way that I read this specification is

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Smalyshev added a comment. It is not wrong, it is in accordance with the standard, please see: https://github.com/wikimedia/mediawiki-extensions-Wikibase/blob/master/repo/includes/Rdf/Values/GlobeCoordinateRdfBuilder.php#L57 Yes, you need to account in your parsing of literals that some c

[Wikidata-bugs] [Maniphest] [Commented On] T129072: wikibase:geoGlobe IRI included in simple value geo:wktLiteral for non-Earth coordinates

Christopher added a comment. Intentional or not., It is wrong. Why is it necessary? The problem is that it breaks parsing of geosparql literals. For example, if I ask for instance of volcanoes, I have to make exceptions for weird non-Earth coordinates. TASK DETAIL https://phabricator.wi