- From: Richard Newman <r.newman@reading.ac.uk>
- Date: Sun, 5 Jun 2005 14:38:12 +0100
- To: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
- Cc: patrick.stickler@gmail.com, semantic-web@w3.org
> How can
>
> for all statements [included?] in the subgraph thus far having a
> blank node object, include in the subgraph all statements in the
> source graph where the subject of the statement is the blank node
> in question ...
>
Original graph:
x y [blank node 1];
z a.
x b [blank node 2].
[blank node 1] c d;
e "f".
Initial subgraph (x is target):
x y [blank node 1].
x z a.
x b [blank node 2].
Initial graph contains:
[blank node 1] c d .
[blank node 1] e "f".
So we add these.
** No triples in the initial graph have [blank node 2] as their
subject. We stop. **
The subgraph now contains 5 triples, where the objects are all URIs,
literals, or blank nodes for which there are no statements in the
graph (not the subgraph, the _original_ graph) with that blank node
as the subject.
I.e. the subgraph contains statements about object bnodes if any such
statements exist. If it contains triples pointing to bnodes, and no
statements about those bnodes, it's because the original graph didn't
make any statements about those bnodes.
-R
>
> and
>
> This results in a subgraph where the object nodes are [...], or
> blank nodes not serving as the subject of any statement in the
> graph.
>
> possibly be reconciled?
Received on Sunday, 5 June 2005 13:38:29 UTC