关键词: Generalized shift-splitting, Semi-convergence, Positive definite matrix, Gen-
eralized saddle point problems, Krylov subspace methods

Abstract:  Recently, some authors (Shen and Shi, 2016) studied the generalized shift-
splitting (GSS) iteration method for singular saddle point problem with nonsymmetric
positive definite (1,1)-block and symmetric positive semidefinite (2,2)-block. In this
paper, we further apply the GSS iteration method to solve singular saddle point problem
with nonsymmetric positive semidefinite (1,1)-block and symmetric positive semidefinite
(2,2)-block, prove the semi-convergence of the GSS iteration method and analyze the
spectral properties of the corresponding preconditioned matrix. Numerical experiment is
given to indicate that the GSS iteration method with appropriate iteration parameters is
effective and competitive for practical use.

Key words: Generalized shift-splitting, Semi-convergence, Positive definite matrix, Gen-
eralized saddle point problems, Krylov subspace methods