Package: libbtf1 (1:5.1.2-2)

permutation to block triangular form library for sparse matrices

Suitesparse is a collection of libraries for computations involving sparse matrices.

The BTF library is a software package for permuting a matrix into Block upper Triangular Form. It includes a maximum transversal algorithm, which finds a permutation of a square or rectangular matrix so that it has a zero-free diagonal (if one exists); otherwise, it finds a maximal matching which maximizes the number of nonzeros on the diagonal. The package also includes a method for finding the strongly connected components of a graph. These two methods together give the permutation to block upper triangular form.