Limited approximation of numerical range of normal matrix
نویسندگان
چکیده
منابع مشابه
Limited Approximation of Numerical Range of Normal Matrix
Let A be an n× n normal matrix, whose numerical range NR[A] is a k -polygon. If a unit vector v ∈ W ⊆ Cn, with dimW = k and the point v∗Av ∈ IntNR[A], then NR[A] is circumscribed to NR[P∗AP], where P is an n× (k− 1) isometry of {span{v}}⊥ W → Cn, [1]. In this paper, we investigate an internal approximation of NR[A] by an increasing sequence of NR[Cs] of compressed matrices Cs = R∗s ARs, with R∗...
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ژورنال
عنوان ژورنال: Operators and Matrices
سال: 2010
ISSN: 1846-3886
DOI: 10.7153/oam-04-07