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networkx.generators.expanders.margulis_gabber_galil_graph

margulis_gabber_galil_graph(n, create_using=None)[source]

Returns the Margulis-Gabber-Galil undirected MultiGraph on n^2 nodes.

The undirected MultiGraph is regular with degree 8. Nodes are integer pairs. The second-largest eigenvalue of the adjacency matrix of the graph is at most 5 sqrt{2}, regardless of n.

Parameters:
  • n (int) – Determines the number of nodes in the graph: n^2.
  • create_using (NetworkX graph constructor, optional (default MultiGraph)) – Graph type to create. If graph instance, then cleared before populated.
Returns:

G – The constructed undirected multigraph.

Return type:

graph

Raises:

NetworkXError – If the graph is directed or not a multigraph.