doc updates - converted some examples-in-doc to examples in examples folder

2 files changed, 61 insertions, 0 deletions

diff --git a/examples/smushing.py b/examples/smushing.py
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+++ b/examples/smushing.py
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+"""
+A FOAF smushing example.
+
+Filter a graph by normalizing all ``foaf:Persons`` into URIs based on
+their ``mbox_sha1sum``.
+
+Suppose I got two `FOAF <http://xmlns.com/foaf/0.1>`_ documents each
+talking about the same person (according to ``mbox_sha1sum``) but they
+each used a :class:`rdflib.term.BNode` for the subject. For this demo
+I've combined those two documents into one file:
+
+This filters a graph by changing every subject with a
+``foaf:mbox_sha1sum`` into a new subject whose URI is based on the
+``sha1sum``. This new graph might be easier to do some operations on.
+
+An advantage of this approach over other methods for collapsing BNodes
+is that I can incrementally process new FOAF documents as they come in
+without having to access my ever-growing archive. Even if another
+``65b983bb397fb71849da910996741752ace8369b`` document comes in next
+year, I would still give it the same stable subject URI that merges
+with my existing data.
+
+"""
+
+from rdflib import Graph, Namespace
+from rdflib.namespace import FOAF
+
+STABLE = Namespace("http://example.com/person/mbox_sha1sum/")
+
+if __name__=='__main__':
+    g = Graph()
+    g.parse("smushingdemo.n3", format="n3")
+
+    newURI = {} # old subject : stable uri
+    for s,p,o in g.triples((None, FOAF['mbox_sha1sum'], None)):
+        newURI[s] = STABLE[o]
+
+
+    out = Graph()
+    out.bind('foaf', FOAF)
+
+    for s,p,o in g:
+        s = newURI.get(s, s)
+        o = newURI.get(o, o) # might be linked to another person
+        out.add((s,p,o))
+
+    print out.serialize(format="n3")
diff --git a/examples/smushingdemo.n3 b/examples/smushingdemo.n3
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+++ b/examples/smushingdemo.n3
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+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+
+## from one document
+_:p1 a foaf:Person;
+  foaf:mbox_sha1sum "65b983bb397fb71849da910996741752ace8369b";
+  foaf:nick "mortenf";
+  foaf:weblog <http://www.wasab.dk/morten/blog/archives/author/mortenf/> .
+
+## from another document
+_:p2 a foaf:Person;
+	foaf:mbox_sha1sum "65b983bb397fb71849da910996741752ace8369b";
+	foaf:nick "mortenf";
+	foaf:homepage <http://www.wasab.dk/morten/>;
+	foaf:interest <http://en.wikipedia.org/wiki/Atom_(standard)> .