Results 1 to 10 of about 43 (43)
On new universal realizability criteria
Special Matrices, 2022 A list Λ={λ1,λ2,…,λn}\Lambda =\left\{{\lambda }_{1},{\lambda }_{2},\ldots ,{\lambda }_{n}\right\} of complex numbers is said to be realizable if it is the spectrum of an entrywise nonnegative matrix and is said to be universally realizable (UR), if it is
Arrieta Luis E., Soto Ricardo L.
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Assessing the credibility of the solutions of incomplete-data inverse problems
Physics Open, 2021 This paper proposes an approach to measure the credibility of solutions of inverse problems with incomplete or missing data, encountered in some physical problems.
Aydin M. Torkabadi, Esam M.A. Hussein
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Spectra inhabiting the left half-plane that are universally realizable
Special Matrices, 2021 Let Λ = {λ1, λ2, . . ., λn} be a list of complex numbers. Λ is said to be realizable if it is the spectrum of an entrywise nonnegative matrix. Λ is universally realizable if it is realizable for each possible Jordan canonical form allowed by Λ. Minc ([21]
Soto Ricardo L.
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Permutative universal realizability
Special Matrices, 2021 A list of complex numbers Λ is said to be realizable, if it is the spectrum of a nonnegative matrix. In this paper we provide a new sufficient condition for a given list Λ to be universally realizable (UR), that is, realizable for each possible Jordan ...
Soto Ricardo L. +2 more
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The core inverse and constrained matrix approximation problem
Open Mathematics, 2020 In this article, we study the constrained matrix approximation problem in the Frobenius norm by using the core inverse:||Mx−b||F=minsubjecttox∈ℛ(M),||Mx-b|{|}_{F}=\hspace{.25em}\min \hspace{1em}\text{subject}\hspace{.25em}\text{to}\hspace{1em}x\in ...
Wang Hongxing, Zhang Xiaoyan
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Toeplitz nonnegative realization of spectra via companion matrices
Special Matrices, 2019 The nonnegative inverse eigenvalue problem (NIEP) is the problem of finding conditions for the existence of an n × n entrywise nonnegative matrix A with prescribed spectrum Λ = {λ1, . . ., λn}.
Collao Macarena +2 more
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A recursive condition for the symmetric nonnegative inverse eigenvalue problem
Revista Integración, 2017 In this paper we present a sufficient ondition and a necessary condition for Symmetri Nonnegative Inverse Eigenvalue Problem. This condition is independent of the existing realizability criteria.
Elvis Ronald Valero +2 more
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The Diagonalizable Nonnegative Inverse Eigenvalue Problem
Special Matrices, 2018 In this articlewe provide some lists of real numberswhich can be realized as the spectra of nonnegative diagonalizable matrices but which are not the spectra of nonnegative symmetric matrices.
Cronin Anthony G, Laffey Thomas J.
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Updating a map of sufficient conditions for the real nonnegative inverse eigenvalue problem
Special Matrices, 2019 The real nonnegative inverse eigenvalue problem (RNIEP) asks for necessary and sufficient conditions in order that a list of real numbers be the spectrum of a nonnegative real matrix.
Marijuán C. +2 more
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Numerical construction of structured matrices with given eigenvalues
Special Matrices, 2019 We consider a structured inverse eigenvalue problem in which the eigenvalues of a real symmetric matrix are specified and selected entries may be constrained to take specific numerical values or to be nonzero.
Sutton Brian D.
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