منابع مشابه
Cobra: Parallel path following for computing the matrix pseudospectrum
The construction of an accurate approximation of the-pseudospectrum of a matrix by means of the standard grid method is a very demanding computational task. In this paper, we describe Cobra, a domain-based method for the computation of pseudospectra that combines predictor corrector path following with a one-dimensional grid. The algorithm oers large and medium grain parallelism and becomes pa...
متن کاملBounds for the Componentwise Distance to the Nearest Singular Matrix
The normwise distance of a matrix A to the nearest singular matrix is well known to be equal to ‖A‖/cond(A) for norms being subordinate to a vector norm. However, there is no hope to find a similar formula or even a simple algorithm for computing the componentwise distance to the nearest singular matrix for general matrices. This is because Rohn and Poljak [7] showed that this is an NP -hard pr...
متن کاملComputing the Structured Pseudospectrum of a Toeplitz Matrix and Its Extreme Points
Abstract. The computation of the structured pseudospectral abscissa and radius (with respect to the Frobenius norm) of a Toeplitz matrix is discussed and two algorithms based on a low rank property to construct extremal perturbations are presented. The algorithms are inspired by those considered in [GO11] for the unstructured case, but their extension to structured pseudospectra and analysis pr...
متن کاملSpectrum through pseudospectrum
This report was written in 2001 and it is a translation of work that was originally published in Greek, in the author’s diploma thesis in July 1998. It may contain minor mistakes and should not be considered a complete study. It however touches upon several of the considerations that will be included in the complete paper. The work was done jointly with E. Gallopoulos and was presented at the F...
متن کاملEigenvalues, Pseudospectrum and Structured Perturbations
We investigate the behavior of eigenvalues under structured perturbations. We show that for many common structures such as (complex) symmetric, Toeplitz, symmetric Toeplitz, circulant and others the structured condition number is equal to the unstructured condition number for normwise perturbations, and prove similar results for real perturbations. An exception are complex skewsymmetric matrice...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2004
ISSN: 0024-3795
DOI: 10.1016/j.laa.2003.10.005