Orderings for ILU Preconditioning of Nonsymmetric Problems
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چکیده
Numerical experiments are presented whereby the eeect of reorderings on the convergence of preconditioned Krylov subspace methods for the solution of nonsymmetric linear systems is shown. The preconditioners used in this study are diierent variants of incomplete factorizations. It is shown that reorderings for direct methods, such as Reverse Cuthill-McKee and Minimum Degree, can be very beneecial. The beneet can be seen in the reduction of the number of iterations and also in measuring the appropriate deviation of the preconditioned operator from the identity.
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تاریخ انتشار 1998