Preconditioners for Nondefinite Hermitian Toeplitz Systems
نویسندگان
چکیده
منابع مشابه
Preconditioners for Nondefinite Hermitian Toeplitz Systems
This paper is concerned with the construction of circulant preconditioners for Toeplitz systems arising from a piecewise continuous generating function with sign changes. If the generating function is given, we prove that for any c > 0, only O(log N) eigenvalues of our preconditioned Toeplitz systems of size N xN are not contained in [-1c, -1+c]U [1-c, 1+c). The result can be modified for trigo...
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In this paper we consider solving Hermitian Toeplitz systems Tnx= b by using the preconditioned conjugate gradient (PCG) method. Here the Toeplitz matrices Tn are assumed to be generated by a non-negative continuous 2 -periodic function f, i.e. Tn =Tn[f]. It was proved in (Linear Algebra Appl. 1993; 190:181) that if f is positive then the spectrum of Tn[1=f]Tn[f] is clustered around 1. We prove...
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ژورنال
عنوان ژورنال: SIAM Journal on Matrix Analysis and Applications
سال: 2001
ISSN: 0895-4798,1095-7162
DOI: 10.1137/s0895479899362521