Matrix algebra preconditioners for multilevel Toeplitz systems do not insure optimal convergence rate
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منابع مشابه
Matrix algebra preconditioners for multilevel Toeplitz systems do not insure optimal convergence rate
In the last decades several matrix algebra optimal and superlinear preconditioners (those assuring a strong clustering at the unity) have been proposed for the solution of polynomially ill-conditioned Toeplitz linear systems. The corresponding generalizations for multilevel structures are neither optimal nor superlinear (see e.g. Contemp. Math. 281 (2001) 193). Concerning the notion of superlin...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2004
ISSN: 0304-3975
DOI: 10.1016/j.tcs.2004.01.007