reverse_cuthill_mckee(graph, symmetric_mode=False)
It is assumed by default, symmetric_mode=False
, that the input matrix is not symmetric and works on the matrix A+A.T
. If you are guaranteed that the matrix is symmetric in structure (values of matrix elements do not matter) then set symmetric_mode=True
.
Input sparse in CSC or CSR sparse matrix format.
Is input matrix guaranteed to be symmetric.
Array of permuted row and column indices.
Returns the permutation array that orders a sparse CSR or CSC matrix in Reverse-Cuthill McKee ordering.
>>> from scipy.sparse import csr_matrix
... from scipy.sparse.csgraph import reverse_cuthill_mckee
>>> graph = [
... [0, 1, 2, 0],
... [0, 0, 0, 1],
... [2, 0, 0, 3],
... [0, 0, 0, 0]
... ]
... graph = csr_matrix(graph)
... print(graph) (0, 1) 1 (0, 2) 2 (1, 3) 1 (2, 0) 2 (2, 3) 3
>>> reverse_cuthill_mckee(graph) array([3, 2, 1, 0], dtype=int32)See :
The following pages refer to to this document either explicitly or contain code examples using this.
scipy.sparse.csgraph._reordering.reverse_cuthill_mckee
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