四元数阵重行列式与复阵行列式的关系

指出四元数阵重行列式可用复阵行列式来表示，于是，复阵的伴随矩阵、求逆阵公式、秩的下界等，都可相应地推广到四元数阵．     

一个行列式不等式的进一步研究

本文的日的在于改进已有的两个复矩阵的行列式的上界,以更精细的两个Hermitian正定矩阵和的行列式为基本工具.利用得到的相关一无二次不等式描述的行列式之间的关系,给出了两个复矩阵和的行列式新上界,作为心用可改进华罗庚行列式不等式的上界.     

A bound for the determinant of the sum of two normal matrices

Hadamard's determinant theorem is used to obtain an upper bound for the modulus of the determinant of the sum of two normal matrices in terms of their eigenvalues. This bound is compared with another given by M. E. Miranda.     

Minimax theorems without linear structure

Hadamard's determinant theorem is used to obtain an upper bound for the modulus of the determinant of the sum of two normal matrices in terms of their eigenvalues. This bound is compared with another given by M. E. Miranda.     

四元数体上重行列式的性质及其应用

本文得到了四元数体上重行列式的一些基本不等式，给出了矩阵为正定自共轭阵时，行列式与重行列式的显式关系，同时也给出了文［１］中行列式与文［５］中行列式两种定义的关系。提出了四元数体上广义正定自共轭阵的概念，并获得了这类阵的基本性质．     

A note on certain matrices with h(x) – Fibonacci quaternion polynomials

In this paper we consider a g – circulant, right circulant, left circulant and a special kind of a tridiagonal matrices whose entries are h(x) – Fibonacci quaternion polynomials. We present the determinant of these matrices and with the tridiagonal matrices we show that the determinant is equal to the nth term of the h(x) – Fibonacci quaternion polynomial sequences.     

四元数体上的Vandermonde重行列式

讨论了四元数体上的 Ｖａｎｄｅｒｍｏｎｄｅ 重行列式问题,给出了 Ｖａｎｄｅｒｍｏｎｄｅ 重行列式不为零的充分必要条件·     

四元数矩阵的Jordan标准形

本文是在四元数矩阵的重行列式理论的基础上，直接利用四元数的乘法证明了。任意一个四元数矩阵都相似于特征主值表征的Ｊｏｒｄａｎ标准形及其唯一性．     

实四元数矩阵行列式函数的几点注记

分别对实四元数矩阵理论中出现的几种行列式函数在三个初等变换下的改变性作一些讨论,得出几种满足一定性质的行列式函数的不存在性或唯一存在性。     

Algebraic Methods for Condiagonalization Under Consimilarity of Quaternion Matrices in Quaternionic Quantum Mechanics

By means of complex representation and real representation of quaternion matrices, paper [7] studied the problem of diagonalization of quaternion matrices. This paper introduces two new complex representation and real representation of quaternion matrices, studies the problem of condiagonalization under consimilarity of quaternion matrices, and gives two algebraic methods for the condiagonalization under consimilarity of quaternion matrices.     

四元数矩阵的极分解及其GL偏序

本文给出了四元数矩阵的唯一极分解定理和两个四元数矩阵可同时极分解的两种刻画；进而引进了四元数矩阵的GL偏序的概念，它是重要的Lǒwner偏序的一般化，并得到这个新偏序的6种刻画．     

Definition of determinant and cramer solutions over the quaternion field

A new definition of determinant over the quaternion field is given in this paper Cramer solutions of right (or left) linear equations and the condition of existence of inverse square matrices are obtained from the definition.     

Critical pairs of matrices for the degree of the minimal polynomial of the Kronecker sum

In [4] Dias da Silva and Hamidoune obtained a lower bound for the degree of the minimal polynomial of the Kronecker sum of two matrices in terms of the degrees of the minimal polynomials of the matrices. We determine the pairs of matrices for which this bound is reached.     

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.     

On Complex Split Quaternion Matrices

In this paper, we present some important properties of complex split quaternions and their matrices. We also prove that any complex split quaternion has a 4 × 4 complex matrix representation. On the other hand, we give answers to the following two basic questions “If AB =  I, is it true that BA =  I for complex split quaternion matrices?” and “How can the inverse of a complex split quaternion matrix be found?”. Finally, we give an explicit formula for the inverse of a complex split quaternion matrix by using complex matrices.     

A note on quaternion matrices and split quaternion matrix pencils

In this paper, localization theorems for left and right eigenvalues of a quaternion matrix are presented. Some differences between quaternion matrices and split quaternion matrices are summarized. A counter example for Gerschgorin theorems for left and right eigenvalues of a split quaternion matrix is given. Finally, a method for finding right eigenvalues of a split quaternion matrix pencil is presented.     

A simplification of Stenger's topological degree formula

Summary A formula due to F. Stenger expresses the topological degree of a continuous mapping defined on a polyhedron inR ⁿ as a constant times a sum of determinants ofn×n matrices. We replace these determinant evaluations by a scanning procedure which examines their associated matrices and at each ofn–1 steps discards at least half of the matrices remaining from the previous step. Finally we obtain a lower bound for the number of matrices present originally, thus giving an estimate for the minimum amount of labour needed in many cases to compute the degree using this method.     

Location for the right eigenvalues of quaternion matrices

This paper aims to discuss the location for right eigenvalues of quaternion matrices. We will present some different Gerschgorin type theorems for right eigenvalues of quaternion matrices, based on the Gerschgorin type theorem for right eigenvalues of quaternion matrices (Zhang in Linear Algebra Appl. 424:139?C153, 2007), which are used to locate the right eigenvalues of quaternion matrices. We shall conclude this paper with some easily computed regions which are guaranteed to include the right eigenvalues of quaternion matrices in 4D spaces.     

Equality constrained least squares problem over quaternion field

By using complex representation and GSVD of quaternion matrices, we define the norm of quaternion matrices, study the equality constrained least squares problem of quaternion matrices, give the necessary and sufficient conditions for the quaternion equality constrained least squares problem to have solutions, and finally derive a practical algorithm.     

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.