Results 11 to 20 of about 52 (51)

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., Pisonero M., Soto Ricardo L.   +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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The Direct and Inverse Spectral Problems for some Banded Matrices [PDF]

, 2011
2000 Mathematics Subject Classification: 15A29.In this paper we introduced a notion of the generalized spectral function for a matrix J = (gk,l)k,l = 0 Ґ, gk,l О C, such that gk,l = 0, if |k-l | > N; gk,k+N = 1, and gk,k-N № 0. Here N is a fixed positive
Zagorodnyuk, S. M.
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Regular Graphs of Degree at most Four that Allow Two Distinct Eigenvalues

, 2023
For an $n \times n$ matrix $A$, let $q(A)$ be the number of distinct eigenvalues of $A$. If $G$ is a connected graph on $n$ vertices, let $\mathcal{S}(G)$ be the set of all real symmetric $n \times n$ matrices $A=[a_{ij}]$ such that for $i\neq j$, $a_{ij}
Tait, Michael, Fallat, Shaun, Rooney, Brendan, Furst, Veronika, Barrett, Wayne, Nasserasr, Shahla   +5 more
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1-Sylvester matrices

Special Matrices
A nonzero element aa is called 1-Sylvester in a ring RR, if there exist b,c∈Rb,c\in R such that 1=ab+ca1=ab+ca. In this article, we study such elements, mainly in matrix rings over commutative rings.
Călugăreanu Grigore
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Pygmalion and His Ivory Maiden in Twenty-first Century Science Fiction

Dictynna
This paper explores how one manufactured woman in Greco-Roman myth, Pygmalion's ivory maiden in Ovid's Metamorphoses, has shaped the production of synthetic women in recent science fiction.
Hunter H. Gardner
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On the existence of optimal set-valued decoders and their accuracy bounds for ill-posed inverse problems

European Journal of Applied Mathematics
Ill-posed inverse problems occur everywhere in the sciences, including medical imaging, radar, astronomy, etc., yielding underdetermined or ill-posed linear (non-linear) reconstruction problems.
Nina Maria Gottschling, Paolo Campodonico, Vegard Antun, Anders C. Hansen   +3 more
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Universal realizability of left half-plane spectra

Special Matrices
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 AA. The list Λ\Lambda is diagonalizably realizable (Dℛ{
Soto Ricardo L., Salas Mario, Villagra Juan J.   +2 more
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Una condición recursiva para el problema inverso del autovalor para matrices simétricas no negativas

, 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.
Lenes, Eber, Mallea Zepeda, Exequiel, Valero, Elvis Ronald   +2 more
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