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Block matrices and symmetric perturbations

✍ Scribed by Alicja Smoktunowicz

Publisher: Elsevier Science
Year: 2008
Tongue: English
Weight: 120 KB
Volume: 429
Category: Article
ISSN: 0024-3795
DOI: 10.1016/j.laa.2008.03.013

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✦ Synopsis

We prove that if A = [A ij ] ∈ R N,N is a block symmetric matrix and y is a solution of a nearby linear system (A + E)y = b, then there exists F = F T such that y solves a nearby symmetric system (A + F )y = b, if A is symmetric positive definite or the matricial norm μ(A) = ( A ij 2 ) is diagonally dominant. Our blockwise analysis extends existing normwise and componentwise results on preserving symmetric perturbations (cf. [

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