Results 1 to 10 of about 156 (29)
Singular matrices that are products of two idempotents or products of two nilpotents
Special Matrices, 2021 Over commutative domains we characterize the singular 2 × 2 matrices which are products of two idempotents or products of two nilpotents. The relevant casees are the matrices with zero second row and the singular matrices with only nonzero entries.
Călugăreanu Grigore
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Combined matrix of diagonally equipotent matrices
Special Matrices, 2023 Let C(A)=A∘A−T{\mathcal{C}}\left(A)=A\circ {A}^{-T} be the combined matrix of an invertible matrix AA, where ∘\circ means the Hadamard product of matrices.
Bru Rafael +4 more
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Special Matrices, 2021 We propose an algorithm, which is based on the method given by Kişi and Özdemir in [Math Commun, 23 (2018) 61], to handle the problem of when a linear combination matrix X=∑i=1mciXiX = \sum\nolimits_{i = 1}^m {{c_i}{X_i}} is a matrix such that its ...
Kişi Emre +3 more
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Algebraic conditions and the sparsity of spectrally arbitrary patterns
Special Matrices, 2021 Given a square matrix A, replacing each of its nonzero entries with the symbol * gives its zero-nonzero pattern. Such a pattern is said to be spectrally arbitrary when it carries essentially no information about the eigenvalues of A.
Deaett Louis, Garnett Colin
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Schrödinger’s tridiagonal matrix
Special Matrices, 2021 In the third part of his famous 1926 paper ‘Quantisierung als Eigenwertproblem’, Schrödinger came across a certain parametrized family of tridiagonal matrices whose eigenvalues he conjectured.
Kovačec Alexander
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The expected adjacency and modularity matrices in the degree corrected stochastic block model
Special Matrices, 2018 We provide explicit expressions for the eigenvalues and eigenvectors of matrices that can be written as the Hadamard product of a block partitioned matrix with constant blocks and a rank one matrix.
Fasino Dario, Tudisco Francesco
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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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EURO Journal on Computational Optimization, 2019 The plain Newton-min algorithm for solving the linear complementarity problem (LCP) “0⩽x⊥(Mx+q)⩾0” can be viewed as an instance of the plain semismooth Newton method on the equational version “min(x,Mx+q)=0” of the problem.
Jean-Pierre Dussault +2 more
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A note on completing quasi-distance and distance matrices
Special Matrices, 2019 We give a necessary and sufficient condition for the existence of a quasi-distance matrix where some positive off-diagonal entries have been prescribed. Moreover, we give an algorithm for obtaining such a matrix.
Zhang Yulin +2 more
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Some spectral bounds for the harmonic matrix
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2017 The aim of this note is to establish new spectral bounds for the harmonic matrix.
Das Kinkar Ch., Fonseca Carlos M. da
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