Modified Newton-AGSOR method for solving nonlinear systems with block two-by-two complex symmetric Jacobian matrices

Abstract

In this paper, we modify the accelerated generalized successive overrelaxation (AGSOR) method for block two-by-two complex linear systems, and use the AGSOR method as an inner iteration for the modified Newton equations to solve the nonlinear system whose Jacobian matrix is a block two-by-two complex symmetric matrix. Our new method is named modified Newton AGSOR (MN-AGSOR) method. Because generalized successive overrelaxation (GSOR) method is a special form of the AGSOR method, the modified Newton GSOR (MN-GSOR) method is also analyzed in the discussion. Next, we use the Holder continuous condition instead of the Lipschitz assumption to analyze and prove the local convergence properties of the MN-AGSOR method. At last, numerical experiments verify the efficiency of the MN-AGSOR method, and it can be seen from the comparison of various aspects that the MN-AGSOR method is superior to some other recently proposed methods.