Results 1 to 10 of about 40 (30)
Graph complement conjecture for classes of shadow graphs
Operators and Matrices, 2021 The real minimum semidefinite rank of a graph G , denoted mrR+(G) , is defined to be the minimum rank among all real symmetric positive semidefinite matrices whose zero/nonzero pattern corresponds to the graph G .
Monsikarn Jansrang, S. Narayan
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A note on two-sided removal and cancellation properties associated with Hermitian matrix
, 2021 A complex square matrix A is said to be Hermitian if A = A∗, the conjugate transpose of A. We prove that each of the two triple matrix product equalities AA∗A = A∗AA∗ and A3 = AA∗A implies that A is Hermitian by means of decompositions and determinants
Yongge Tian
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Cospectral constructions for several graph matrices using cousin vertices
Special Matrices, 2021 Graphs can be associated with a matrix according to some rule and we can find the spectrum of a graph with respect to that matrix. Two graphs are cospectral if they have the same spectrum.
Lorenzen Kate
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Combinatorial properties of the enhanced principal rank characteristic sequence over finite fields
Special Matrices, 2021 The enhanced principal rank characteristic sequence (epr-sequence) of a symmetric matrix B ∈ 𝔽n×n is defined as ℓ1ℓ2· · · ℓn, where ℓj ∈ {A, S, N} according to whether all, some but not all, or none of the principal minors of order j of B are nonzero ...
Dukes Peter J., Martínez-Rivera Xavier
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Fast iterative solutions of Riccati and Lyapunov equations
Open Mathematics, 2022 In this article, new iterative algorithms for solving the discrete Riccati and Lyapunov equations are derived in the case where the transition matrix is diagonalizable with real eigenvalues.
Assimakis Nicholas, Adam Maria
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The complete positivity of symmetric tridiagonal and pentadiagonal matrices
Special Matrices, 2022 We provide a decomposition that is sufficient in showing when a symmetric tridiagonal matrix AA is completely positive. Our decomposition can be applied to a wide range of matrices.
Cao Lei, McLaren Darian, Plosker Sarah
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Perturbation bounds for matrix functions
, 2020 In this article, we present some bounds for ||| f (A)− f (B)||| , where f is a real function and is continuously differentiable on an open interval J , |||·||| is a unitarily invariant norm, and A,B are Hermitian matrices such that the eigenvalues of A ...
M. Masoudi, A. Salemi
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Special Matrices, 2021 In the study of eigenvalues, multiplicities, and graphs, the minimum number of multiplicities equal to 1 in a real symmetric matrix with graph G, U(G), is an important constraint on the possible multiplicity lists among matrices in 𝒮(G).
Ding Wenxuan, Johnson Charles R.
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Skew-symmetric matrices related to the vector cross product in ℂ7
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2023 Skew-symmetric matrices of order 7 defined through the 2-fold vector cross product in ℂ7, and other related matrices, are presented. More concretely, matrix properties, namely invertibility, nullspace, powers and index, are studied.
Beites P. D. +2 more
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Sufficient conditions for symmetric matrices to have exactly one positive eigenvalue
Special Matrices, 2020 Let A = [aij] be a real symmetric matrix. If f : (0, ∞) → [0, ∞) is a Bernstein function, a sufficient condition for the matrix [f (aij)] to have only one positive eigenvalue is presented.
Al-Saafin Doaa, Garloff Jürgen
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