Results 1 to 10 of about 219 (51)
Equality in Wielandt’s eigenvalue inequality
Special Matrices, 2015 In this paper we give necessary and sufficient conditions for the equality case in Wielandt’s eigenvalue inequality.
Friedland Shmuel
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A matrix-algebraic algorithm for the Riemannian logarithm on the Stiefel manifold under the canonical metric [PDF]
SIAM Journal on Matrix Analysis and Applications, 2017 We derive a numerical algorithm for evaluating the Riemannian logarithm on the Stiefel manifold with respect to the canonical metric. In contrast to the existing optimization-based approach, we work from a purely matrix-algebraic perspective.
Zimmermann, Ralf
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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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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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Trace inequalities for positive semidefinite matrices
Discussiones Mathematicae - General Algebra and Applications, 2017 Certain trace inequalities for positive definite matrices are generalized for positive semidefinite matrices using the notion of the group generalized inverse.
Choudhury Projesh Nath, Sivakumar K.C.
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Orthogonal Representations, Projective Rank, and Fractional Minimum Positive Semidefinite Rank: Connections and New Directions [PDF]
, 2017 Fractional minimum positive semidefinite rank is defined from r-fold faithful orthogonal representations and it is shown that the projective rank of any graph equals the fractional minimum positive semidefinite rank of its complement.
Hogben, L +3 more
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