laplacian_matrix#

laplacian_matrix(G, nodelist=None, weight='weight')[source]#

Returns the Laplacian matrix of G.

The graph Laplacian is the matrix L = D - A, where A is the adjacency matrix and D is the diagonal matrix of node degrees.

Parameters:
Ggraph

A NetworkX graph

nodelistlist, optional

The rows and columns are ordered according to the nodes in nodelist. If nodelist is None, then the ordering is produced by G.nodes().

weightstring or None, optional (default=’weight’)

The edge data key used to compute each value in the matrix. If None, then each edge has weight 1.

Returns:
LSciPy sparse matrix

The Laplacian matrix of G.

See also

to_numpy_array
normalized_laplacian_matrix
laplacian_spectrum

Notes

For MultiGraph, the edges weights are summed.