Block Triangular Form (BTF) (sksparse.btf)

Added in version 0.5.0.

Python interface to the Block Triangular Format (BTF) library.

Interface

maxtrans(A)	Compute the maximum transversal of a sparse matrix.
strongcomp(A[, q])	Compute the strongly connected components of a directed graph.
btf(A)	Permute the square sparse matrix into Block Triangular Form (BTF).
btf_q_permutation(q)	Convert a raw BTF column permutation vector to a valid permutation.

References

• SuiteSparse homepage

• SuiteSparse BTF

• Duff, Iain. “On Algorithms for Obtaining a Maximum Transversal”, ACM Trans. Mathematical Software, vol 7, no. 1, pp. 315-330.

• “Algorithm 575: Permutations for a Zero-Free Diagonal”, ACM Trans. Mathematical Software, vol 7, no. 1, pp. 387-390. Algorithm 575 is MC21A in the Harwell Subroutine Library.