Diagonal-schur complements of SDD1 matrices
摘要
Diagonal-Schur complement is a hot topic in Matrix theory. The class of SDD1 matrices is an important subclass of nonsingular H-matrices. In this paper, we prove that the diagonal-Schur complements of SDD1 matrices are also SDD1 matrices with respect to any principal sub-matrix. We introduce the concept of the corresponding diagonally dominant degree. Then the SDD1 diagonally dominant degrees of diagonal-Schur complements are estimated. The numerical results are reported.