0000000000948383
AUTHOR
ÓScar Romero
Algorithms for solving the inverse problem associated with KAK =A^(s+1)
In previous papers, the authors introduced and characterized a class of matrices called {K,s+1}-potent. Also, they established a method to construct these matrices. The purpose of this paper is to solve the associated inverse problem. Several algorithms are developed in order to find all involutory matrices K satisfying K A^(s+1) K = A for a given matrix A∈C^(n×n) and a given natural number s. The cases s=0 and s≥ are separately studied since they produce different situations. In addition, some examples are presented showing the numerical performance of the methods.
Relations between {K, s + 1}-potent matrices and different classes of complex matrices
In this paper, {K,s+1}-potent matrices are considered. A matrix A∈C^(n×n) is called {K,s+1}-potent when K A^(s+1) K = A where K is an involutory matrix and s∈{1,2,3,¿}. Specifically, {K,s+1}-potent matrices are analyzed considering their relations to different classes of complex matrices. These classes of matrices are: {s+1}-generalized projectors, {K}-Hermitian matrices, normal matrices, and matrices B∈C^(n×n) (anti-)commuting with K or such that KB is involutory, Hermitian or normal. In addition, some new relations for K-generalized centrosymmetric matrices have been derived.