Title
Eigenvalue clustering of coefficient matrices in the iterative stride reductions for linear systems.
Abstract
Solvers for linear systems with tridiagonal coefficient matrices sometimes employ direct methods such as the Gauss elimination method or the cyclic reduction method. In each step of the cyclic reduction method, nonzero offdiagonal entries in the coefficient matrix move incrementally away from diagonal entries and eventually vanish. The steps of the cyclic reduction method are generalized as forms of the stride reduction method. For example, the 2-stride reduction method coincides with the 1st step of the cyclic reduction method which transforms tridiagonal linear systems into pentadiagonal systems. In this paper, we explain arbitrary-stride reduction for linear systems with coefficient matrices with three nonzero bands. We then show that arbitrary-stride reduction is equivalent to a combination of 2-stride reduction and row and column permutations. We thus clarify eigenvalue clustering of coefficient matrices in the step-by-step process of the stride reduction method. We also provide two examples verifying this property.
Year
DOI
Venue
2016
10.1016/j.camwa.2015.11.022
Computers & Mathematics with Applications
Keywords
Field
DocType
Stride reduction,Linear system,Coefficient matrix,Block diagonal,Eigenvalue clustering
Tridiagonal matrix,Mathematical optimization,Coefficient matrix,Linear system,Mathematical analysis,Matrix (mathematics),Gaussian elimination,Cyclic reduction,Eigenvalues and eigenvectors,Block matrix,Mathematics
Journal
Volume
Issue
ISSN
71
1
0898-1221
Citations 
PageRank 
References 
0
0.34
7
Authors
4
Name
Order
Citations
PageRank
Munehiro Nagata110.81
Masatsugu Hada200.34
Masashi Iwasaki3279.42
Yoshimasa Nakamura44817.38