[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.12941/jksiam.2019.23.267

ON REDUCTION OF K-ALMOST NORMAL AND K-ALMOST CONJUGATE NORMAL MATRICES TO A BLOCK TRIDIAGONAL FORM

ASIL, K. NIAZI (DEPARTMENT OF MATHEMATICS, LORESTAN UNIVERSITY)
KAMALVAND, M. GHASEMI (DEPARTMENT OF MATHEMATICS, LORESTAN UNIVERSITY)

Publication Information

Journal of the Korean Society for Industrial and Applied Mathematics / v.23, no.3, 2019 , pp. 267-282 More about this Journal

Abstract

This paper examines how one can build a block tridiagonal structure for k-almost normal matrices and also for k-almost conjugate normal matrices. We shall see that these representations are created by unitary similarity and unitary congruance transformations, respectively. It shall be proven that the orders of diagonal blocks are 1, k + 2, 2k + 3, ${\ldots}$ , in both cases. Then these block tridiagonal structures shall be reviewed for the cases where the mentioned matrices satisfy in a second-degree polynomial. Finally, for these processes, algorithms are presented.

Keywords

k-almost normal matrix; k-almost conjugate normal matrix; block tridiagonal matrix;

Citations & Related Records

Reference

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