This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.

# GraphUnion

 GraphUnion gives the graph union of the graphs and . GraphUniongives 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:
 Out[1]=

With different vertices:
 Out[1]=
 Scope   (3)
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