Point template

spec.bs

@@ -8,7 +8,7 @@ Repository: KNowledgeOnWebScale/rdf-timeseriessnippets
 URL: https://knowledgeonwebscale.github.io/rdf-timeseriessnippets/
 Editor: Dylan Van Assche, https://dylanvanassche.be/#me
 Editor: Pieter Colpaert, https://pietercolpaert.be
-Abstract: An RDF Time Series Snippet is a segment of data points from a time series dataset, typically used for analysis or visualization. The specification uses JSON to store the data points to allow re-usability of existing tooling for analyzing time series. The entity can then be used for annotating this snippet, which is a time interval subset of a potentially larger time series.
+Abstract: An RDF Time Series Snippet is a segment of data points from a time series dataset, typically used for analysis or visualization. The specification uses JSON data types for the data points. This allows re-usability of existing tooling for analyzing or visualizing these time series snippet literals, for whih the RDF provides useful context information.
 Markup Shorthands: markdown yes, css no
 </pre>
 
@@ -35,25 +35,24 @@ A first example illustrates the features of a `tss:Snippet`:
     { "time": "2026-01-01T06:00:00Z", "value": "5.4", "id": "https://example.org/0"},
     { "time": "2026-01-01T06:59:59Z", "value": "5.2", "id": "https://example.org/1"},
     { "time": "2026-01-01T08:00:00Z", "value": "5.2", "id": "https://example.org/2"},
-    { "time": "2026-01-01T09:00:00Z", "value": "6.1", "id": "https://example.org/3"},
+    { "time": "2026-01-01T09:00:00Z", "value": "6.1", "id": "https://example.org/3"}
   ]"""^^rdf:JSON;
   tss:from "2026-01-01T00:00:00Z"^^xsd:dateTime;
   tss:until "2026-01-02T00:00:00Z"^^xsd:dateTime;
   tss:pointType sosa:Observation;
-  tss:context """{
-    "@context":{
-       "time": {
-         "@id":"http://www.w3.org/ns/sosa/resultTime",
-         "@type":"http://www.w3.org/2001/XMLSchema#dateTime"
-     },
-     "value": {
-         "@id":"http://www.w3.org/ns/sosa/simpleValue",
-         "@type":"http://www.w3.org/2001/XMLSchema#integer"
-      },
-     "id": "@id"
-    }
-  }"""^^rdf:JSON;
-  tss:about [
+  tss:context """
+      "@context":{
+	   "time": {
+	        "@id":"sosa:resultTime",
+	        "@type":"xsd:dateTime"
+	   },
+	   "value": {
+	        "@id":"sosa:resultTime",
+	        "@type":"xsd:integer"
+	   }
+       }
+  """^^rdf:JSON;
+  tss:about [ a tss:PointTemplate;
     sosa:madeBySensor <temp_sensor_1>;
     sosa:observedProperty <temperature>;
   ];
@@ -111,7 +110,7 @@ Each [=Snippet=] SHOULD have the following properties:
 - `tss:points`: a JSON array (datatype `rdf:JSON`) of data points where each data point is a JSON object with a `time` key using `xsd:dateTime` value, with a `value` key for which the value is annotated with a datatype, and optionally an `id` key for which the value is an IRI for the current data point.
 - `tss:from`: starting timestamp (including) of the period covered by `tss:points` using an `xsd:dateTime`.
 - `tss:until`: until this timestamp (excluding) of the period covered by `tss:points` using an `xsd:dateTime`.
-- `tss:about`: contains statements about a blank node. The statements can be asserted on top of all data points in `tss:points` when expanding the Snippet.
+- `tss:about`: contains statements the data points, defined as a `tss:PointTemplate`. The statements can be asserted on top of all data points in `tss:points` when expanding the Snippet.
 - `tss:pointType`: the RDF type of all data points in `tss:points`.
 - `tss:context`: JSON-LD context describing the JSON array of `tss:points`.
 
@@ -131,7 +130,7 @@ Each [=Data Point=] itself MUST be a JSON object consisting of 2 required proper
     { "time": "2026-01-01T06:00:00Z", "value": "5.4", "id": "https://example.org/0" },
     { "time": "2026-01-01T06:59:59Z", "value": "5.2", "id": "https://example.org/1" },
     { "time": "2026-01-01T08:00:00Z", "value": "5.2", "id": "https://example.org/2" },
-    { "time": "2026-01-01T09:00:00Z", "value": "6.1", "id": "https://example.org/3" },
+    { "time": "2026-01-01T09:00:00Z", "value": "6.1", "id": "https://example.org/3" }
 ]"""^^rdf:JSON;
 ```
 </div>
@@ -152,11 +151,11 @@ When the optional JSON-LD context is provided through `tss:context`, a [=Snippet
  } 
 }
 ```
+
 The properties `tss:about` and `tss:pointType` will influence that process.
 
 For each [=Data Point=], it can be mapped as follows:
- 1. When the `id` is set and it is a valid IRI, set this id as the subject. If it is not, create a new blank node and set this as the subject.
- 2. When `tss:pointType` is set, create a triple stating this id is of `rdf:type` the object of the pointType triple.
- 3. Create a triple for the time based on the JSON-LD context. For unknown intermediary named nodes, a blank node is to be created.
- 4. Similarly, create a triple for the value based on the JSON-LD context.
- 5. Now apply the `tss:about` blank node entity to this point.
+ 1. Use the JSON-LD process to convert the given JSON to RDF using the JSON-LD context.
+ 2. For each entity (which may be a blank node or an IRI), 
+     - When `tss:pointType` is set, create a triple stating this id is of `rdf:type` the object of the pointType triple.
+     - When `tss:about` is set, apply the subject-based star pattern of the template, except for the type, to this entity.

tss.ttl

@@ -94,3 +94,10 @@ tss:Snippet rdf:type owl:Class ;
     rdfs:comment "RDF Time Series Snippet"@en;
     rdfs:isDefinedBy <>;
 .
+
+###  https://w3id.org/tss/PointTemplate
+tss:PointTemplate rdf:type owl:Class ;
+    rdfs:label "PointTemplate";
+    rdfs:comment "RDF Time Series Point Template"@en;
+    rdfs:isDefinedBy <>;
+.