四元数体上矩阵的广义对角化

引入了复四元数环和四元数体上矩阵可 对角化的概念,研究了复四元数环上矩阵的性质,给出了四元数体上矩阵可 对角化的充分必要条件和求矩阵 对角化的方法。     

四元数矩阵的新特征值定位

Yin Caixia;Li Chaoqian(College of Mathematics and Statistics,Yunnan University,Kunming 650500,China)     

四元数矩阵的Lwner偏序

对于 A,B∈ H( n,≥ ) ,该文给出 Lowner偏序下 A≤ L B的五种刻画和 A2 ≤ L B2 的两种刻画 ;并将 A,B∈C( n,* )时 ,A≤ L B的 Liski定理推广到四元数除环上 .     

Schur定理在四元数体上的推广

In this paper，we show that every matrix over the real quaternion division ring is unitary similar to an upper triangular matrix.     

四元数体上的矩阵及其优化理论

本文引入了四元数体 Q 上的广义双随机矩阵,给出了它与优化的关系.由此,我们得出了四元数矩阵奇异值的一些重要不等式,特别是得出了四元数矩阵的和与积的奇异值不等式.我们还讨论了四元数自共轭矩阵的和与积的特征值等.推广了复数域上矩阵的许多著名结果.     

四元数体上的矩阵分解

本文将复数域上矩阵的积因子分解推广到四元数体上。     

广义四元数体上矩阵的最小多项式

本文给出了广义四元数体上方阵的最小多项式与最小中心多项式的构造公式，讨论了它们的性质及其应用，得到广义四元数方阵相似于对角矩阵的一个充要条件。     

关于四元数矩阵乘积迹的不等式

设 H~(m×n)为 m×n 四元数矩阵的集合,σ_1(A)≥…≥σ_n(A)为 A∈H~(mxn)的奇异值。本文证明了:1)设 A∈H~(mxm),B∈H~(mxm),r=min(m,m),则|tr(4B)|≤c r σ_i(A)σ_i(B).2)设 A_i∈H~(mxm),i=1,2,…,n,(A_1A_2…A_n)k为 A_1A_2…A_n 的任一个 k 阶主子阵,则|tr(A_1.A_2…A_n)_k|≤sun form i=1 to k σ_i(A_1)…σ_i(A_n).我们还得到四元数矩阵迹的其它一些不等式。这些结果推广和改进了文[1],[2]中的结果,进一步解决了 Bellman 猜想。     

四元数自共轭矩阵特征值的不等式

本文证明了四元数矩阵特征值的几个重要的不等式,推广了文［１］、［２］的结果．     

一个四元数矩阵方程的可解性

§ 1　 IntroductionL et R be the real number field,C=R Ri be the complex numberfield,and H=C Cj=R Ri Rj Rk be the quaternion division ring over R,where k:=ij=- ji,i2 =j2 =k2 =- 1 .Ifα=a1 +a2 i+a3 j+a4 k∈ H ,where ai∈ R,then letα=a1 - a2 i- a3 j- a4 k bethe conjugate ofα.L et Hm× nbe the setof all m× n matrices over H.If A=(aij)∈ Hn× n ,L etATbe the transpose matrix of A,A be the conjugate matrix of A,and A* =(aij) T be thetranspose conjugate matrix of A.A∈Hn× nis said…     

四元数矩阵方程AX+YA=C的两种最佳逼近解

利用四元数矩阵的广义Frobenius范数建立一个关于四元数矩阵的实函数,并讨论了它的极值问题,然后在四元数矩阵方程AX YA=C的一般解和自共轭解集合中分别导出了与给定相同类型矩阵的最佳逼近解的表达式.     

On the eigenvalues of quaternion matrices

This article is a continuation of the article [F. Zhang, Ger?gorin type theorems for quaternionic matrices, Linear Algebra Appl. 424 (2007), pp. 139–153] on the study of the eigenvalues of quaternion matrices. Profound differences in the eigenvalue problems for complex and quaternion matrices are discussed. We show that Brauer's theorem for the inclusion of the eigenvalues of complex matrices cannot be extended to the right eigenvalues of quaternion matrices. We also provide necessary and sufficient conditions for a complex square matrix to have infinitely many left eigenvalues, and analyse the roots of the characteristic polynomials for 2?×?2 matrices. We establish a characterisation for the set of left eigenvalues to intersect or be part of the boundary of the quaternion balls of Ger?gorin.     

用迭代方法解一类特殊的矩阵方程

本主要研究解矩阵方程AX YB=D和AX XB=D的一种迭代方法．     

一对四元数矩阵方程的共轭延拓解

定义广义四元数共轭延拓矩阵的概念,利用矩阵分块和四元数矩阵的实表示方法,分别给出四元数矩阵方程AX=C和XB=D存在列共轭延拓解和行共轭延拓解的必要充分条件及解的表达式.     

四元数体上一类矩阵方程的极小范数最小二乘解

借助于四元数体上自共轭矩阵的奇异值分解,给出了四元数矩阵方程AX＋XB＋CXD=F的极小范数最小二乘解.同时,在有解的条件下给出了Hermite最小二乘解及其通解的表达形式.     

Numerical analysis of a quadratic matrix equation

The quadratic matrix equation AX²+ BX + C = 0in n x nmatricesarises in applications and is of intrinsic interest as oneof the simplest nonlinear matrix equations. We give a completecharacterization of solutions in terms of the generalized Schurdecomposition and describe and compare various numerical solutiontechniques. In particular, we give a thorough treatment offunctional iteration methods based on Bernoulli’s method.Other methods considered include Newton’s method with exact line searches, symbolic solution and continued fractions.We show that functional iteration applied to the quadraticmatrix equation can provide an efficient way to solve the associated quadratic eigenvalue problem (²A + B + C)x = 0.     

On modified block SSOR iteration methods for linear systems from steady incompressible viscous flow problems

In order to solve the large sparse systems of linear equations arising from numerical solutions of two-dimensional steady incompressible viscous flow problems in primitive variable formulation, we present block SSOR and modified block SSOR iteration methods based on the special structures of the coefficient matrices. In each step of the block SSOR iteration, we employ the block LU factorization to solve the sub-systems of linear equations. We show that the block LU factorization is existent and stable when the coefficient matrices are block diagonally dominant of type-II by columns. Under suitable conditions, we establish convergence theorems for both block SSOR and modified block SSOR iteration methods. In addition, the block SSOR iteration and AF-ADI method are considered as preconditioners for the nonsymmetric systems of linear equations. Numerical experiments show that both block SSOR and modified block SSOR iterations are feasible iterative solvers and they are also effective for preconditioning Krylov subspace methods such as GMRES and BiCGSTAB when used to solve this class of systems of linear equations.     

四元数矩阵方程(AXB,CXD)=(E,F)的最小范数最小二乘Hermitian解

提出了研究四元数矩阵方程(AXB, CXD)=(E, F)的最小范数最小二乘Hermitian解的一个有效方法.首先应用四元数矩阵的实表示矩阵以及实表示矩阵的特殊结构,把四元数矩阵方程转化为相应的实矩阵方程,然后求出四元数矩阵方程(AXB, CXD)=(E, F)的最小二乘Hermitian解集,进而得到其最小范数最小二乘Hermitian解.所得到的结果只涉及实矩阵,相应的算法只涉及实运算,因此非常有效.最后的两个数值例子也说明了这一点.