A Sparse Approximate Inverse Preconditioner for Nonsymmetric Positive Definite Matrices
نویسندگان
چکیده
We develop an algorithm for computing a sparse approximate inverse for a nonsymmetric positive definite matrix based upon the FFAPINV algorithm. The sparse approximate inverse is computed in the factored form and used to work with some Krylov subspace methods. The preconditioner is breakdown free and, when used in conjunction with Krylovsubspace-based iterative solvers such as the GMRES algorithm, results in reliable solvers. Some numerical experiments are given to show the efficiency of the preconditioner. AMS Mathematics Subject Classification : 65F10, 65F50.
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