How to check isomorphism across subgraphs

Question

I want to check for isomorphism across subgraphs in a larger dataset. Is there a way to do this in rdflib without breaking the graph into multiple variables, like in the example from rdflib docs:

g1 = Graph().parse(format='n3', data='''
     @prefix : <http://example.org/ns#> .
     []:rel <http://example.org/a> ;
      :rel <http://example.org/b> ;
      :rel [ :label "A bnode." ] .
 ''')
 g2 = Graph().parse(format='n3', data='''
     @prefix ns: <http://example.org/ns#> .
     []:rel <http://example.org/a> ;
      :rel <http://example.org/b> ;
      :rel [ :label "A bnode." ] .
 ''')
isomorphic(g1, g2)

my graph

[]:rel <http://example.org/a> ;
      :rel <http://example.org/b> ;
      :rel [ :label "A bnode." ] .

[]:rel <http://example.org/a> ;
      :rel <http://example.org/c> ;
      :rel [ :label "A bnode." ] .

[]:rel <http://example.org/a> ;
      :rel <http://example.org/b> ;
      :rel [ :label "A bnode." ] .

Thanks for any help!

score 1 · Accepted Answer · answered Jul 10 '20 at 10:37

Sorry but I don't think there's really a way to do this. The graphs within a Dataset aren't really available on their own - you have to get to them through the graph - so you can't do something like:


# no function get_graph
ds.get_graph(identifier="http://eg.org/a")\
    .isomorphic(ds.get_graph(identifier="http://eg.org/b"))

# or 

# no function get_graph
isomorphic(
    ds.get_graph(identifier="http://eg.org/a"),
    ds.get_graph(identifier="http://eg.org/b"),
)

Perhaps we - RDFlib maintainers - should add a function to export a Graph out of a Dataset... — Nicholas Car, Jul 14 '20 at 06:01

How to check isomorphism across subgraphs

1 Answers1