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Related papers: Companion unit lower Hessenberg matrices

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Companion matrices of the second type are characterized by properties that involve bilinear maps.

Numerical Analysis · Mathematics 2016-01-26 Minghua Lin , Harald K. Wimmer

Theoretical analysis of biological and artificial neural networks e.g. modelling of synaptic or weight matrices necessitate consideration of the generic real-asymmetric matrix ensembles, those with varying order of matrix elements e.g. a…

Disordered Systems and Neural Networks · Physics 2025-09-15 Ratul Dutta , Pragya Shukla

We study random matrices with independent subgaussian columns. Assuming each column has a fixed Euclidean norm, we establish conditions under which such matrices act as near-isometries when restricted to a given subset of their domain. We…

Probability · Mathematics 2025-09-05 Yaniv Plan , Roman Vershynin

Sparse modeling is a powerful framework for data analysis and processing. Traditionally, encoding in this framework is done by solving an l_1-regularized linear regression problem, usually called Lasso. In this work we first combine the…

Information Theory · Computer Science 2010-03-02 Pablo Sprechmann , Ignacio Ramirez , Guillermo Sapiro , Yonina C. Eldar

We analyze the set of real and complex Hadamard matrices with additional symmetry constrains. In particular, we link the problem of existence of maximally entangled multipartite states of $2k$ subsystems with $d$ levels each to the set of…

Quantum Physics · Physics 2024-06-18 Wojciech Bruzda , Grzegorz Rajchel-Mieldzioć , Karol Życzkowski

In this paper, we describe a new algorithm that approximates the extreme eigenvalue/eigenvector pairs of a symmetric matrix. The proposed algorithm can be viewed as an extension of the Jacobi eigenvalue method for symmetric matrices…

Numerical Analysis · Mathematics 2025-09-16 Cristian Rusu

In this paper we generalize the canonical positive scaling of rows and columns of a matrix to the scaling of selected-rank subtensors of an arbitrary tensor. We expect our results and framework will prove useful for sparse-tensor completion…

Numerical Analysis · Mathematics 2020-09-03 Tung D. Nguyen , Jeffrey Uhlmann

We show that some modern geometric methods of Hamiltonian dynamics can be directly applied to the nonholonomic Heisenberg type systems. As an example we present characteristic Killing tensors, compatible Poisson brackets, Lax matrices and…

Exactly Solvable and Integrable Systems · Physics 2016-11-28 Yury A. Grigoryev , Alexey P. Sozonov , Andrey V. Tsiganov

Semipositive matrices (matrices that map at least one nonnegative vector to a positive vector) and minimally semipositive matrices (semipositive matrices whose no column-deleted submatrix is semipositive) are well studied in matrix theory.…

Functional Analysis · Mathematics 2018-06-20 Projesh Nath Choudhury , M. Rajesh Kannan , K. C. Sivakumar

Haagerup's proof of the non commutative little Grothendieck inequality raises some questions on the commutative little inequality, and it offers a new result on scalar matrices with non negative entries. The theory of completely bounded…

Functional Analysis · Mathematics 2024-04-05 Erik Christensen

Inhomogeneous random matrices with non-trivial variance profiles determined by symmetric stochastic matrices and with independent sub-Gaussian entries up to Hermitian symmetry, encompass a wide range of important models, including sparse…

Probability · Mathematics 2026-02-24 Ruohan Geng , Dang-Zheng Liu , Guangyi Zou

Nonnegative matrix factorization is a powerful technique to realize dimension reduction and pattern recognition through single-layer data representation learning. Deep learning, however, with its carefully designed hierarchical structure,…

Computer Vision and Pattern Recognition · Computer Science 2017-07-31 Zhenxing Guo , Shihua Zhang

Boundary integral equations lead to dense system matrices when discretized, yet they are data-sparse. Using the $\mathcal{H}$-matrix format, this sparsity is exploited to achieve $\mathcal{O}(N\log N)$ complexity for storage and…

Numerical Analysis · Mathematics 2025-05-22 Kobe Bruyninckx , Daan Huybrechs , Karl Meerbergen

An associative central simple algebra is a form of matrices, because a maximal \'{e}tale subalgebra acts on the algebra faithfully by left and right multiplication. In an attempt to extract and isolate the full potential of this point of…

Rings and Algebras · Mathematics 2023-12-11 Guy Blachar , Darrell Haile , Eliyahu Matzri , Edan Rein , Uzi Vishne

In this note, we consider matrices similar to $X$-form matrices, which are the matrices for which only the diagonal and the anti-diagonal elements can be different from zero. First, we give a characterization of these matrices using the…

Rings and Algebras · Mathematics 2023-08-31 Flavien Mabilat

A universal R--matrix for the quantum Heisenberg algebra h(1)q is presented. Despite of the non--quasitriangularity of this Hopf algebra, the quantum group induced from it coincides with the quasitriangular deformation already known.

High Energy Physics - Theory · Physics 2009-10-28 A. Ballesteros , Enrico Celeghini , F. J. Herranz , M. A. del Olmo , M. Santander

We consider approximating solutions to parameterized linear systems of the form $A(\mu_1,\mu_2) x(\mu_1,\mu_2) = b$. Here the matrix $A(\mu_1,\mu_2) \in \mathbb{R}^{n \times n}$ is nonsingular, large, and sparse and depends nonlinearly on…

Numerical Analysis · Mathematics 2025-02-27 Siobhán Correnty , Melina A. Freitag , Kirk M. Soodhalter

We use techniques from (tracial noncommutative) polynomial optimization to formulate hierarchies of semidefinite programming lower bounds on matrix factorization ranks. In particular, we consider the nonnegative rank, the positive…

Optimization and Control · Mathematics 2018-11-06 Sander Gribling , David de Laat , Monique Laurent

Non-negative matrix factorization models based on a hierarchical Gamma-Poisson structure capture user and item behavior effectively in extremely sparse data sets, making them the ideal choice for collaborative filtering applications.…

Machine Learning · Computer Science 2016-05-27 Mehmet E. Basbug , Barbara E. Engelhardt

Generalization theory has been established for sparse deep neural networks under high-dimensional regime. Beyond generalization, parameter estimation is also important since it is crucial for variable selection and interpretability of deep…

Machine Learning · Statistics 2024-06-27 Dongya Wu , Xin Li