Computation of pseudospectra via spectral projectors
نویسنده
چکیده
In this note, we discuss new techniques for analyzing the pseudospectra of matrices and propose a numerical method for computing the spectral projector associated with a group of eigenvalues enclosed by a polygonal curve. Numerital tests are reported.
منابع مشابه
A reduced basis approach to large-scale pseudospectra computation
For studying spectral properties of a non-normal matrix A ∈ Cn×n, information about its spectrum σ(A) alone is usually not enough. Effects of perturbations on σ(A) can be studied by computing ε-pseudospectra, that is the level-sets of the resolvent norm function g(z) = ‖(zI−A)‖2. The computation of ε-pseudospectra requires determining the smallest singular values σmin(zI − A) on for all z on a ...
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