Approximate Inverse Preconditioning for Shifted Linear Systems
نویسندگان
چکیده
In this paper we consider the problem of preconditioning symmetric positive definite matrices of the form Aα = A+αI where α > 0. We discuss how to cheaply modify an existing sparse approximate inverse preconditioner for A in order to obtain a preconditioner for Aα. Numerical experiments illustrating the performance of the proposed approaches are presented. AMS subject classification (2000): 65F10, 65N22, 15A18.
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