An Augmentation Preconditioner for Asymmetric Saddle Point Problems with Singular (1,1) Blocks
نویسندگان
چکیده
Abstract In this paper, an augmentation preconditioner for asymmetric saddle point problems with singular (1,1) blocks is introduced on the base of the recent article by He and Huang [Two augmentation preconditioners for nonsymmetric and indefinite saddle point linear systems with singular (1, 1) blocks, Comput. Math. Appl., 62 (2011) 87-92]. We study the spectral characteristics of the preconditioned matrix in detail. Theoretical analysis shows that all the eigenvalues of the preconditioned matrix are strongly clustered. Numerical experiments are given to demonstrate the efficiency of the presented preconditioner.
منابع مشابه
A New Preconditioner with Two Variable Relaxation Parameters for Saddle Point Linear Systems with Highly Singular(1,1) Blocks
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