Hi Oliver, I have an idea for why this may not be working for you, but I'd rather respond to a question on StackOverflow (https://stackoverflow.com/questions/ask) tagged with the "rdflib" tag added (rdflib should autocomplete in the tags input), as this email list is for technical matters relating to the RDFLib software, not usage questions.
I just checked that I am subscribed to email notifications for new [rdflib] questions (https://stackoverflow.com/questions/tagged/rdflib) on StackOverflow. If I don't respond to your question soon, feel free to email me directly to get on it. :) Best, Donny On Friday, May 20, 2022 at 8:13:53 AM UTC-7 Olivier Inizan wrote: > Hi there, > > I am trying to play with rdflib and a (my) user defined vocabulary (name: > ODE). > To do that I have generated a class namespace/_ODE.py derived from > DefinedNamespace: > 1 from rdflib.term import URIRef > 2 from rdflib.namespace import DefinedNamespace, Namespace > 3 > 4 > 5 class ODE(DefinedNamespace): > 6 """ > 7 DESCRIPTION_EDIT_ME_! > 8 > 9 Generated from: SOURCE_RDF_FILE_EDIT_ME_! > 10 Date: 2022-05-02 08:38:55.619901 > 11 """ > 12 > 13 _fail = True > 14 > 15 Function: URIRef > 16 Equation: URIRef > 17 hasDerivative: URIRef > 18 Polynomial: URIRef > 19 Ode: URIRef > 20 > 21 _NS = Namespace("ode#") > 22 > > As all the new "classes" of the ODE vocabulary are a specialization of the > class "Seq" I have created the module rdflib/ode.py: > > 1 from rdflib import Seq > 2 from rdflib.namespace import RDF,ODE,MATH > 3 > 4 __all__ = ["Function", "Equation","Polynomial","Ode"] > 5 > 6 > 7 class Ode(Seq): > 8 def __init__(self, graph, uri, seq=[], rtype="Ode"): > 9 """Creates a Container > 10 > 11 :param graph: a Graph instance > 12 :param uri: URI or Blank Node of the Container > 13 :param seq: the elements of the Container > 14 :param rtype: the type of Container, one of "Bag", "Seq" or > "Alt" > 15 """ > 16 > 17 self.graph = graph > 18 self.uri = uri or BNode() > 19 self._len = 0 > 20 self._rtype = rtype # rdf:Bag or rdf:Seq or rdf:Alt > 21 > 22 self.append_multiple(seq) > 23 > 24 # adding triple corresponding to container type > 25 self.graph.add((self.uri, RDF.type, ODE[self._rtype])) > 26 > 27 class Function(Ode): > 28 def __init__(self, graph, uri, seq=[]): > 29 Ode.__init__(self, graph, uri, seq, "Function") > 30 > 31 > 32 class Equation(Ode): > 33 def __init__(self, graph, uri, seq=[]): > 34 Ode.__init__(self, graph, uri, seq, "Equation") > 35 > 36 class Polynomial(Ode): > 37 def __init__(self, graph, uri, seq=[]): > 38 Ode.__init__(self, graph, uri, seq, "Polynomial") > > With these two classes I can generate a RDF file in a declarative way. > For example we can create the Function c(t): > 1 from rdflib import Graph, URIRef, RDF, BNode, RDFS, Literal, Seq, Bag, > Function, Equation, Times, Minus, Polynomial, Ode > 2 from rdflib.namespace import ODE, MATH > 3 > 4 # the time t > 5 t = BNode("t") > 6 graph.add((t,RDFS.label,Literal("t"))) > 7 > 8 c_of_t_label = BNode("c") > 9 graph.add((c_of_t_label,RDFS.label,Literal("c"))) > 10 c_of_t_bn = BNode("c_of_t") > 11 > 12 Function(graph,c_of_t_bn,[c_of_t_label,t]) > > And we obtain the following RDF: > _:c rdfs:label "c" . > _:t rdfs:label "t" . > _:c_of_t a ode:Function ; > rdf:_1 _:c ; > rdf:_2 _:t . > > So far, so good. Now I want to execute a SPARQL query on this rdf to > retrieve the function. > > > > 1 import rdflib > 2 > 3 from rdflib import Graph, URIRef, RDF, BNode, RDFS, Literal, Seq, Bag, > Function, Equation, Times, Minus, Polynomial, Ode > 4 from rdflib.namespace import ODE, MATH > 5 > 6 def main(): > 7 g = rdflib.Graph() > 8 g.parse("ode_spe", format="ttl") > 9 > 10 > 11 function = ODE.Function > 12 > 13 query_test= "SELECT ?e WHERE {?e rdf:type ode:Function . }" > 14 qres = g.query(query_test) > 15 > 16 print (len(qres)) > 17 if __name__ == "__main__": > 18 main() > > But I have no results. > I probably do not do the right thing with ode:Function. > > I have two questions: > - Is it the right way to add a user defined vocabulary ? > - And what can I do to retrieve the function with a SPARQL query > > Thank for your help. > > Olivier > -- http://github.com/RDFLib --- You received this message because you are subscribed to the Google Groups "rdflib-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to rdflib-dev+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rdflib-dev/a8f751c5-00f0-4e95-ba2f-61710b60f69dn%40googlegroups.com.
