Results 1 to 10 of about 1,108 (78)
An ℋ-tensor-based criteria for testing the positive definiteness of multivariate homogeneous forms
Open Mathematics, 2022 A positive definite homogeneous multivariate form plays an important role in the field of optimization, and positive definiteness of the form can be identified by a special structured tensor.
Bai Dongjian, Wang Feng
doaj +1 more source
Eigenvalue inclusion sets for linear response eigenvalue problems
Demonstratio Mathematica, 2022 In this article, some inclusion sets for eigenvalues of a matrix in the linear response eigenvalue problem (LREP) are established. It is proved that the inclusion sets are tighter than the Geršgorin-type sets.
He Jun, Liu Yanmin, Lv Wei
doaj +1 more source
On Regular Signed Graphs with Three Eigenvalues
Discussiones Mathematicae Graph Theory, 2020 In this paper our focus is on regular signed graphs with exactly 3 (distinct) eigenvalues. We establish certain basic results; for example, we show that they are walk-regular.
Anđelić Milica +2 more
doaj +1 more source
Open Mathematics, 2021 Positive definite polynomials are important in the field of optimization. ℋ-tensors play an important role in identifing the positive definiteness of an even-order homogeneous multivariate form.
Sun Deshu, Bai Dongjian
doaj +1 more source
A modified variant of HSS preconditioner for generalized saddle point problems
Advances in Mechanical Engineering, 2022 Recently, Zhang [Numerical Linear Algebra with Applications, 2018: e2166] constructed an efficient variant of Hermitian and skew-Hermitian splitting (HSS) preconditioner for generalized saddle point problems, and gave the corresponding theoretical ...
Li-Tao Zhang, Yi-Fan Zhang
doaj +1 more source
A new generalized shift-splitting method for nonsymmetric saddle point problems
Advances in Mechanical Engineering, 2022 Recently, Huang and Huang [ Journal of Computational and Applied Mathematics , 328 (2018) 381–399] proposed a modified generalized shift-splitting preconditioned (denoted by MGSSP) method for solving large sparse saddle point problems, and gave the ...
Tao Wei, Li-Tao Zhang
doaj +1 more source
Tridiagonal test matrices for eigenvalue computations : two-parameter extensions of the Clement matrix [PDF]
, 2016 The Clement or Sylvester-Kac matrix is a tridiagonal matrix with zero diagonal and simple integer entries. Its spectrum is known explicitly and consists of integers which makes it a useful test matrix for numerical eigenvalue computations.
Oste, Roy, Van der Jeugt, Joris
core +2 more sources
Improved Cauchy radius for scalar and matrix polynomials [PDF]
, 2017 We improve the Cauchy radius of both scalar and matrix polynomials, which is an upper bound on the moduli of the zeros and eigenvalues, respectively, by using appropriate polynomial multipliers.Comment: 12 ...
Berrington, Janet +12 more
core +4 more sources
Perturbations in a Signed Graph and its Index
Discussiones Mathematicae Graph Theory, 2018 In this paper we consider the behaviour of the largest eigenvalue (also called the index) of signed graphs under small perturbations like adding a vertex, adding an edge or changing the sign of an edge.
Stanić Zoran
doaj +1 more source
On the Yang-Baxter-like matrix equation for rank-two matrices
Open Mathematics, 2017 Let A = PQT, where P and Q are two n × 2 complex matrices of full column rank such that QTP is singular. We solve the quadratic matrix equation AXA = XAX.
Zhou Duanmei, Chen Guoliang, Ding Jiu
doaj +1 more source