The QR algorithm for unitary Hessenberg matrices
Journal of Computational and Applied Mathematics
On Smooth Decompositions of Matrices
SIAM Journal on Matrix Analysis and Applications
Eigenvalue computation for unitary rank structured matrices
Journal of Computational and Applied Mathematics
Unitary rank structured matrices
Journal of Computational and Applied Mathematics
A multiple shift QR-step for structured rank matrices
Journal of Computational and Applied Mathematics
Chasing Bulges or Rotations? A Metamorphosis of the QR-Algorithm
SIAM Journal on Matrix Analysis and Applications
Hi-index | 7.29 |
In an earlier paper we introduced the classes of polynomial and rank structures, both of them preserved by applying a (shifted) QR-step on a matrix A. In the present paper we further investigate the case of rank structures. We show that even if A is a singular matrix, a new QR-iterate can be constructed having the same rank structure as the matrix A itself. To this end we introduce the concepts of effectively eliminating QR-decompositions and sparse Givens patterns, both of them being of independent interest.