New insights in GMRES-like methods with variable preconditioners
نویسنده
چکیده
In this paper we compare two recently proposed methods, FGMRES 5] and GMRESR 7], for the iterative solution of sparse linear systems with an unsymmetric nonsingular matrix. Both methods compute minimal residual approximations using preconditioners, which may be diierent from step to step. The insights resulting from this comparison lead to better variants of both methods.
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