union#
- union(G, H, rename=())[source]#
Combine graphs G and H. The names of nodes must be unique.
A name collision between the graphs will raise an exception.
A renaming facility is provided to avoid name collisions.
- Parameters:
- G, Hgraph
A NetworkX graph
- renameiterable , optional
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”.
- Returns:
- UA union graph with the same type as G.
See also
Notes
To combine graphs that have common nodes, consider compose(G, H) or the method, Graph.update().
disjoint_union() is similar to union() except that it avoids name clashes by relabeling the nodes with sequential integers.
Edge and node attributes are propagated from G and H to the union graph. Graph attributes are also propagated, but if they are present in both G and H, then the value from H is used.
Examples
>>> G = nx.Graph([(0, 1), (0, 2), (1, 2)]) >>> H = nx.Graph([(0, 1), (0, 3), (1, 3), (1, 2)]) >>> U = nx.union(G, H, rename=("G", "H")) >>> U.nodes NodeView(('G0', 'G1', 'G2', 'H0', 'H1', 'H3', 'H2')) >>> U.edges EdgeView([('G0', 'G1'), ('G0', 'G2'), ('G1', 'G2'), ('H0', 'H1'), ('H0', 'H3'), ('H1', 'H3'), ('H1', 'H2')])