This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.1)

GraphUnion

GraphUnion
gives the graph union of the graphs and .
GraphUnion
gives the graph union of , , ....
The graph union of two graphs with some vertices being the same:
With different vertices:
The graph union of two graphs with some vertices being the same:
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Click for copyable input
Out[1]=
 
With different vertices:
In[1]:=
Click for copyable input
Out[1]=
GraphUnion works with undirected graphs:
Directed graphs:
GraphUnion works with more than two graphs:
The vertices of the graph union are the union of the vertices of the graphs:
The edges of the graph union are the union of the edges of the graphs:
The graph union of a graph and its subgraph is isomorphic to itself:
The graph union of any simple graph and its complement is a complete graph:
The GraphUnion of two graphs has the same vertices as GraphDifference:
The GraphUnion of two graphs has the same vertices as GraphIntersection:
The GraphDisjointUnion can be found using GraphUnion:
The adjacency matrix for a disjoint union corresponds to the block-diagonal of adjacency matrices:
New in 8