14:33:33 RRSAgent has joined #hcls 14:33:37 logging to https://www.w3.org/2024/06/06-hcls-irc 14:33:38 rrsagent, make logs public 14:36:58 Meeting: FHIR RDF 14:37:01 Chair: David Booth 15:05:20 Topic: DICOM 15:11:59 eric: If you use a sentinal or a bnode, either approach would not work well for OWL. 15:13:44 ... If you use a sentinal w a string type instead of xsd:datetime (for example) then OWL would be okay, but you would lose the datetime datatype. 15:15:30 jim: Now when we transform RDF lists we just change the property names from the rdf: namespace to soemthng else. 15:17:28 dbooth: RDF list ladders are the wrong way to do arrays. They should have indexes. 15:18:21 eric: SPARQL 1.2 might add mechanisms to get indexes from RDF lists. 15:18:46 jim: Are they doing anything to make property paths more powerful? 15:18:48 eric: IDK 15:19:28 erich: I don't want to break reasoning. 15:21:37 dbooth: FHIR RDF R5 already breaks OWL reasoning, but we have a workaround to convert data to be owl friendly. 15:24:02 detlef: Most of the time I need all of the values of the array, with the ordering. 15:24:29 eric: Some toolkits give a way to return an RDF list as an array. 15:27:22 erich: I access individual list elements in SPARQL. 15:27:45 .. Implemented parts of geo SPARQL. 15:28:12 ... Using polygons for filtering in SPARQL. 15:28:38 ... Data is too much for a single triplestore. Using Apache Arrow with Jena. 15:29:16 ... Federated SPARQL query, bring together data from different layers. 15:29:50 ... Code is public: BeakGraph 15:30:03 https://github.com/ebremer/BeakGraph 15:30:16 erich: Named graphs are mapped to Arrow chunks. 15:30:36 ... Hilbert pyramid 15:31:06 ... Client side I pull reduced ersolution ploygons. 15:32:24 ... DICOM 2.2 brigns pathology into it, but no mechanisms for spatial indexing 15:32:37 ... Can't do performant viewing without indexing. 15:33:04 eric: You're using geosparql? 15:33:39 erich: Yes. I'm generating geosparql to represent the polygon in text form. Then BeakGraph is what the system actually uses. 15:34:11 eric: But you're not using sparql to pick a diagnoal through a cube? 15:35:08 erich: IDK 15:36:20 eric: When you use extension fns in sparql, you can take advantage of your engine donig someting optimal. I don't think you'd be using std sparql to look at diagnoal slices without using extension functions. 15:36:53 erich: You can do simple cube queries, but after that you'll need extensions. 15:37:16 eric: I wouldn't have to be stored as an RDF list. 15:39:01 https://halcyon.readthedocs.io/en/latest/docs/annotations.html 15:42:46 erich: IDK how often these nulls show up. 15:44:12 eric: I like bnode with a sentinal type. 15:45:04 ... Bare sentinals (without bnode standoff) make sparql more complex. 15:46:30 detlef: Usually it's just an empty string if its null. 15:46:48 ... But HL7 has dozens of null flavors, but I dont' think they're in DICOM. 15:50:03 dbooth: What if we had a bnode, with attached null type, that sounds easiest for sparql. Then it would need conversion to work for OWL. 15:54:01 ACTION: Eric to add option 10 for representing null as bnode with type that indicates null flavor. 15:54:22 https://github.com/w3c/hcls-fhir-rdf/issues/141 15:56:27 TallTed has joined #hcls 16:01:09 ADJOURNED 17:49:48 rrsagent, draft minutes 17:49:49 I have made the request to generate https://www.w3.org/2024/06/06-hcls-minutes.html dbooth 17:50:40 Present: Detlef Grittner, Erich Bremer, EricP, Jim Balhoff, David Booth 17:50:43 rrsagent, draft minutes 17:50:45 I have made the request to generate https://www.w3.org/2024/06/06-hcls-minutes.html dbooth 19:51:46 MacTed has joined #hcls