Results 31 to 40 of about 535,226 (278)

A Family of Maximal Algebras of Block Toeplitz Matrices

Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2018
The maximal commutative subalgebras containing only Toeplitz matrices have been identified as generalized circulants. A similar simple description cannot be obtained for block Toeplitz matrices.
Khan Muhammad Ahsan
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Elementary triangular matrices and inverses of k-Hessenberg and triangular matrices

Special Matrices, 2015
We use elementary triangular matrices to obtain some factorization, multiplication, and inversion properties of triangular matrices. We also obtain explicit expressions for the inverses of strict k-Hessenberg matrices and banded matrices. Our results can
Verde-Star Luis
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Constructing positive maps from block matrices

, 2013
Positive maps are useful for detecting entanglement in quantum information theory. Any entangled state can be detected by some positive map. In this paper, the relation between positive block matrices and completely positive trace-preserving maps is ...
Fan, Heng, Guo, Yu
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Dynamical System Stability Criteria Based on the Frobenius Norm

AppliedMath
It is well known that the position of the Jacobian matrix spectrum in the left-half complex plane provides the local asymptotic stability of a nonlinear dynamical system, but it is also well known that for large matrices, computing its eigenvalues just ...
Dragana Cvetković, Ernest Šanca
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Spectral problem of block-rectangular hierarchical matrices

, 2010
The spectral problem for matrices with a block-hierarchical structure is often considered in context of the theory of complex systems. In the present article, a new class of matrices with a block-rectangular non-symmetric hierarchical structure is ...
Gutkin, B., Osipov, V. Al.
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Block Diagonal Matrices [PDF]

Formalized Mathematics, 2008
Summary. In this paper I present basic properties of block diagonal matrices over a set. In my approach the finite sequence of matrices in a block diagonal matrix is not restricted to square matrices. Moreover, the o-diagonal blocks need not be zero matrices, but also with another arbitrary fixed value.
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Block Jacobi matrices and Titchmarsh-Weyl function [PDF]

Opuscula Mathematica
We collect some results and notions concerning generalizations for block Jacobi matrices of several concepts, which have been important for spectral studies of the simpler and better known scalar Jacobi case.
Marcin Moszyński, Grzegorz Świderski
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On Factorization and Calculation of Determinant of Block Matrices with Triangular Submatrices

Journal of New Theory
In this paper, we consider some block matrices of dimension $nm\times{nm}$ whose components are triangular matrices of dimension $n\times{n}$. We prove that the determinant of such block matrices is determined only by the diagonal elements of their ...
Fatma Altun, Ufuk Kaya
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Eigenvectors of block circulant and alternating circulant matrices [PDF]

, 2005
The eigenvectors and eigenvalues of block circulant matrices had been found for real symmetric matrices with symmetric submatrices, and for block circulant matrices with circulant submatrices. The eigenvectors are now found for general block circulant
Tee, Garry J.
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Block-circulant complex Hadamard matrices

Journal of Mathematical Physics, 2023
A new method of obtaining a sequence of isolated complex Hadamard matrices (CHM) for dimensions N ⩾ 7, based on block-circulant structures, is presented. We discuss several analytic examples resulting from a modification of the Sinkhorn algorithm. In particular, we present new isolated matrices of orders 9, 10, and 11, which elements are not roots of ...
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