Results 11 to 20 of about 37,446 (199)
Clusters, preconditioners, convergence
Linear Algebra and its Applications, 1997 The authors address the problem of clusterization of singular values. In this context, they present a technique that relates the existence of clusters of singular values to the existence of clusters of eigenvalues. This clusterization technique is based on the notion of regular preconditioners for a sequence of complex matrices.
Eugene E. Tyrtyshnikov +2 more
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A Preconditioner for the Ohta--Kawasaki Equation [PDF]
SIAM Journal on Matrix Analysis and Applications, 2017 We propose a new preconditioner for the Ohta--Kawasaki equation, a nonlocal Cahn--Hilliard equation that describes the evolution of diblock copolymer melts. We devise a computable approximation to the inverse of the Schur complement of the coupled second-order formulation via a matching strategy.
Farrell, Patrick E., Pearson, John
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Approximate eigenvectors as preconditioner
Linear Algebra and its Applications, 2000 Given approximate eigenvector matrix of a Hermitian nonsingular matrix H, the spectral decomposition of H can be obtained by computing H´=*H and then diagonalizing H´. This work addresses the issue of numerical stability of the transition from H to H´ in finite precision arithmetic.
Krešimir Veselić, Zlatko Drmač
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Preconditioners for nonconforming discretizations [PDF]
Mathematics of Computation, 1996 We prove an abstract norm equivalence for a two-level method, which allows us to reduce the construction of preconditioners for nonconforming finite element discretizations to known cases of conforming elements.
Peter Oswald, Peter Oswald
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A theory of secant preconditioners [PDF]
Mathematics of Computation, 1993 In this paper we analyze the use of structured quasi-Newton formulae as preconditioners of iterative linear methods when the inexact-Newton approach is employed for solving nonlinear systems of equations. We prove that superlinear convergence and bounded work per iteration is obtained if the preconditioners satisfy a Dennis-Moré condition. We develop a
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A Preconditioner for Improved Fermion Actions [PDF]
Nuclear Physics B - Proceedings Supplements, 1999 SSOR preconditioning of fermion matrix inversions which is parallelized using a locally-lexicographic lattice sub-division, has been shown to be very efficient for standard Wilson fermions. We demonstrate here the power of this method for the Sheikholeslami-Wohlert improved fermion action and for a renormalization group improved action incorporating ...
Andreas Frommer +5 more
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A dimension expanded preconditioning technique for block two-by-two linear equations
Demonstratio Mathematica, 2023 In this article, we introduce a novel block preconditioner for block two-by-two linear equations by expanding the dimension of the coefficient matrix. Theoretical results on the eigenvalues distribution of the preconditioned matrix are obtained, and a ...
Luo Wei-Hua, Carpentieri Bruno, Guo Jun
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AIMS Mathematics, 2022 In this work, by introducing a scalar matrix αI, we transform the complex symmetric indefinite linear systems (W+iT)x=b into a block two-by-two complex equations equivalently, and propose an efficient relaxed shift-splitting (ERSS) preconditioner.
Qian Li, Qianqian Yuan, Jianhua Chen
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A note on T. Chan’s preconditioner
Linear Algebra and its Applications, 2004 This paper shows that T. Chan's preconditioner matrix [SIAM J. Sci. Stat. Comput. 9, No. 4, 766--771 (1988; Zbl 0646.65042)] is stable for some special class of matrices i.e. matrices that are *-congruent to a stable diagonal matrix. By using this result, the authors prove the invertibility of some preconditioners proposed in the numerical solution of ...
Mingchao Cai, Xiao-Qing Jin
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The BPS preconditioner on Beowulf cluster [PDF]
Revista de Matemática: Teoría y Aplicaciones, 2009 This work presents the implementation on a Linux Cluster of a parallel preconditioner for the solution of the linear system resulting from the finite element discretization of a 2D second order elliptic boundary value problem. The numerical method, proposed by Bramble, Pasciak and Schatz, is developed using Domain Decomposition techniques, which are ...
O Salas +4 more
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