Companion matrices: reducibility, numerical ranges and similarity to contractions
| dc.citation.epage | 142 | en_US |
| dc.citation.issue | en_US | |
| dc.citation.spage | 127 | en_US |
| dc.citation.volume | 383 | en_US |
| dc.citation.woscount | 14 | |
| dc.contributor.author | Gau, HL | en_US |
| dc.contributor.author | Pei, YW | en_US |
| dc.contributor.department | 應用數學系 | zh_TW |
| dc.contributor.department | Department of Applied Mathematics | en_US |
| dc.date.accessioned | 2014-12-08T15:39:10Z | |
| dc.date.available | 2014-12-08T15:39:10Z | |
| dc.date.issued | 2004-05-15 | en_US |
| dc.description.abstract | In this paper, we study some unitary-equivalence properties of the companion matrices. We obtain a criterion for a companion matrix to be reducible and show that the numerical range of a companion matrix is circular disc centered at the origin if and only if the matrix equals the (nilpotent) Jordan block. However, the more general assertion that a companion matrix is determined by its numerical range turns out to be false. We also determine, for an n x n matrix A with eigenvalues in the open unit disc, the defect index of a contraction to which A is similar. (C) 2004 Elsevier Inc. All rights reserved. | en_US |
| dc.identifier.doi | 10.1016/S0024-3795(03)00887-5 | en_US |
| dc.identifier.issn | 0024-3795 | en_US |
| dc.identifier.journal | LINEAR ALGEBRA AND ITS APPLICATIONS | en_US |
| dc.identifier.uri | http://dx.doi.org/10.1016/S0024-3795(03)00887-5 | en_US |
| dc.identifier.uri | https://ir.lib.nycu.edu.tw/handle/11536/26770 | |
| dc.identifier.wosnumber | WOS:000221377100013 | |
| dc.language.iso | en_US | en_US |
| dc.subject | companion matrix | en_US |
| dc.subject | reducible matrix | en_US |
| dc.subject | numerical range | en_US |
| dc.subject | defect index | en_US |
| dc.title | Companion matrices: reducibility, numerical ranges and similarity to contractions | en_US |
| dc.type | Article | en_US |