Mixed Graph
A mixed graph in which both directed and undirected edges may exist.
If only directed edges exist, the graph is called a directed graph.
If only undirected edges exist, it is called an undirected graph.
See also
Directed Graph, Multigraph, Pseudograph, Simple Graph, Undirected GraphExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Mixed Graph." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/MixedGraph.html