8.2 Graph Predicates & Properties
predicate
(graph-named? val) → boolean?
val : graph?
Return #t if graph was created as a named graph.
predicate
(graph-empty? val) → boolean?
val : graph?
Return #t if this graph contains no statements.
predicate
(graph-has-duplicates? val) → boolean?
val : graph?
Returns #t if the graph has duplicate statements.
procedure
(graph-count graph) → exact-positive-integer?
graph : graph?
Returns the number of statements in the graph, this does not take into account whether there are duplicate statements.
procedure
(graph-order graph) → exact-positive-integer?
graph : graph?
Returns the order of the graph, or the number of vertices. For RDF a vertex is defined as any
resource? or blank-node? in the graph.
procedure
(graph->distinct-graph graph) → graph?
graph : graph?
Returns a new graph where the list of statements in the source graph have been removed. The name of
the source is also preserved in the new copy.