SSDD Matrices and Relations with Other Subclasses of the Nonsingular ℋ-Matrices
摘要
The paper introduces into consideration a new matrix class of the so-called SSDD (Schur SDD) matrices, which contains the class of SDD (strictly diagonally dominant) matrices and is itself contained in the class of nonsingular ℋ-matrices. The definition of an SSDD matrix A is based on distinguishing a subset S of its strictly diagonally dominant rows and requiring that the Schur complement ℳ(A)/S of its comparison matrix be an SDD matrix. Properties of SSDD matrices and their relations with other subclasses of the class of ℋ-matrices are considered. In particular, it is shown that such known matrix classes as those of OB, SOB, DZ, DZT (DZ-type), CKV-type, S-SDD, SDD1, SDDk, GSDD1, and also