An example illustrating how to use the
Graph.transitive_subjects and
Graph.transitive_objects graph methods
Formal definition
The Graph.transitive_objects method finds all
nodes such that there is a path from subject to one of those nodes
using only the predicate property in the triples. The
Graph.transitive_subjects method is similar; it
finds all nodes such that there is a path from the node to the object
using only the predicate property.
Informal description, with an example
In brief, Graph.transitive_objects walks forward
in a graph using a particular property, and
Graph.transitive_subjects walks backward. A good
example uses a property ex:parent, the semantics of which are
biological parentage. The
Graph.transitive_objects method would get all
the ancestors of a particular person (all nodes such that there is a
parent path between the person and the object). The
Graph.transitive_subjects method would get all
the descendants of a particular person (all nodes such that there is a
parent path between the node and the person). So, say that your URI is
ex:person.
This example would get all of your (known) ancestors, and then get all the (known) descendants of your maternal grandmother.
Important note on arguments
The Graph.transitive_objects method has the start node
as the first argument, but the Graph.transitive_subjects
method has the start node as the second argument.
User-defined transitive closures
The method Graph.transitiveClosure returns
transtive closures of user-defined functions.
Attributes: