Results 31 to 40 of about 83,251 (167)

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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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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Block diagonalizing ultrametric matrices [PDF]

Journal of Physics A: Mathematical and General, 1994
Title page + 30 pages, Plain Tex using \epsf for 7 figures, ITP.
Temesvári, T., De Dominicis, C., Kondor, I.   +2 more
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On periodic block-tridiagonal matrices

Linear Algebra and its Applications, 1992
Consider an \(N\times N\) tridiagonal matrix \(X\) with entries \(a_1,\ldots,a_N\) down the main diagonal,\(b_1,\ldots, b_{N-1}\) and \(c_1,\ldots,c_{N-1}\) down the super and sub-diagonal files respectively, and zeros elsewhere. Suppose further that the \(a\)-, \(b\)- and \(c\)-sequences are periodic of period \(m\) and that \(N\equiv -1\pmod m ...
ROMANI, FRANCESCO, P. ROZSA
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Block circulant matrices and the spectra of multivariate stationary sequences

Special Matrices, 2021
Given a weakly stationary, multivariate time series with absolutely summable autocovariances, asymptotic relation is proved between the eigenvalues of the block Toeplitz matrix of the first n autocovariances and the union of spectra of the spectral ...
Bolla Marianna, Szabados Tamás, Baranyi Máté, Abdelkhalek Fatma   +3 more
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Link Prediction via Convex Nonnegative Matrix Factorization on Multiscale Blocks

Journal of Applied Mathematics, 2014
Low rank matrices approximations have been used in link prediction for networks, which are usually global optimal methods and lack of using the local information.
Enming Dong, Jianping Li, Zheng Xie
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Block Eigenvalues of block compound matrices

Linear Algebra and its Applications, 1982
AbstractWe obtain some results about the block eigenvalues of block compound matrices and additive block compound matrices. Assuming that a certain block Vandermonde matrix is nonsingular, we generalize known results for (scalar) compound and additive compound matrices.
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Sparse Recovery With Block Multiple Measurement Vectors Algorithm

IEEE Access, 2019
This paper investigates the performance of the block multiple measurement vectors (BMMV) algorithm in reconstructing block joint sparse matrices. We prove that if 41) obeys block restricted isometry property with 8 K+1 <; Nf +1 , then BMMV perfectly ...
Yanli Shi, Libo Wang, Rong Luo
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AN ORDER-P TENSOR MULTIPLICATION WITH CIRCULANT STRUCTURE

Barekeng, 2023
Research on mathematical operations involving multidimensional arrays or tensors has increased along with the growing applications involving multidimensional data analysis. The -product of order-  tensor is one of tensor multiplications.
Itsar Mangngiri, Qonita Qurrota A’yun, Wasono Wasono   +2 more
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