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union(G, H, rename=(None, None), name=None)[source]

Return the union of graphs G and H.

Graphs G and H must be disjoint, otherwise an exception is raised.

  • G,H (graph) – A NetworkX graph
  • rename (bool , default=(None, None)) – Node names of G and H can be changed by specifying the tuple rename=(‘G-‘,’H-‘) (for example). Node “u” in G is then renamed “G-u” and “v” in H is renamed “H-v”.
  • name (string) – Specify the name for the union graph


Return type:

A union graph with the same type as G.


To force a disjoint union with node relabeling, use disjoint_union(G,H) or convert_node_labels_to integers().

Graph, edge, and node attributes are propagated from G and H to the union graph. If a graph attribute is present in both G and H the value from H is used.

See also