Results 21 to 30 of about 524 (74)
Open Mathematics, 2018 In this paper, we introduce the weak group inverse (called as the WG inverse in the present paper) for square complex matrices of an arbitrary index, and give some of its characterizations and properties.
Wang Hongxing, Chen Jianlong
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Maximizing the determinant for a special class of block‐partitioned matrices
Mathematical Problems in Engineering, Volume 2004, Issue 1, Page 49-61, 2004., 2004 An analytical solution is found for the maximum determinant of a block‐partitioned class of matrices with constant trace for each block. As an immediate application of this result, the maximum determinant of a sum of Kronecker products is derived.
Otilia Popescu +2 more
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Direct methods for matrix Sylvester and Lyapunov equations
Journal of Applied Mathematics, Volume 2003, Issue 6, Page 277-303, 2003., 2003 We revisit the two standard dense methods for matrix Sylvester and Lyapunov equations: the Bartels‐Stewart method for A1X + XA2 + D = 0 and Hammarling′s method for AX + XAT + BBT = 0 with A stable. We construct three schemes for solving the unitarily reduced quasitriangular systems. We also construct a new rank‐1 updating scheme in Hammarling′s method.
Danny C. Sorensen, Yunkai Zhou
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Generalized Pell Equations for 2 × 2 Matrices
Discussiones Mathematicae - General Algebra and Applications, 2017 In this paper we consider the solutions of the generalized matrix Pell equations X2 − dY2 = cI, where X and Y are 2 × 2 matrices over ℤ, d is a non-zero (positive or negative) square-free integer, c is an arbitrary integer and I is the 2 × 2 identity ...
Cohen Boaz
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The Cayley transform of Banach algebras
International Journal of Mathematics and Mathematical Sciences, Volume 29, Issue 7, Page 427-428, 2002., 2002 The main result of Haynes (1991) is that a square matrix is convergent (limn→∞Dn = 0) if and only if it is the Cayley transform CA = (I−A)−1(I + A) of a stable matrix A. In this note, we show, with a simple proof, that the above is true in a much more general setting of complex Banach algebras.
Zhidong Pan
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The core inverse and constrained matrix approximation problem
Open Mathematics, 2020 In this article, we study the constrained matrix approximation problem in the Frobenius norm by using the core inverse:||Mx−b||F=minsubjecttox∈ℛ(M),||Mx-b|{|}_{F}=\hspace{.25em}\min \hspace{1em}\text{subject}\hspace{.25em}\text{to}\hspace{1em}x\in ...
Wang Hongxing, Zhang Xiaoyan
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Invariance of recurrence sequences under a galois group
International Journal of Mathematics and Mathematical Sciences, Volume 19, Issue 2, Page 327-334, 1996., 1995 Let F be a Galois field of order q, k a fixed positive integer and R = Fk×k[D] where D is an indeterminate. Let L be a field extension of F of degree k. We identify Lf with fk×1 via a fixed normal basis B of L over F. The F‐vector space Γk(F)( = Γ(L)) of all sequences over Fk×1 is a left R‐module. For any regular f(D) ∈ R, Ωk(f(D)) = {S ∈ Γk(F) : f(D)S
Hassan Al-Zaid, Surjeet Singh
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Solving higher order Fuchs type differential systems avoiding the increase of the problem dimension
International Journal of Mathematics and Mathematical Sciences, Volume 17, Issue 1, Page 91-102, 1994., 1994 In this paper, we develop a Frobenius matrix method for solving higher order systems of differential equations of the Fuchs type. Generalized power series solution of the problem are constructed without increasing the problem dimension. Solving appropriate algebraic matrix equations a closed form expression for the matrix coefficient of the series are ...
E. Navarro, L. Jódar, R. Company
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Generalized Green′s functions for higher order boundary value matrix differential systems
International Journal of Mathematics and Mathematical Sciences, Volume 15, Issue 3, Page 523-535, 1992., 1992 In this paper, a Green′s matrix function for higher order two point boundary value differential matrix problems is constructed. By using the concept of rectangular co‐solution of certain algebraic matrix equation associated to the problem, an existence condition as well as an explicit closed form expression for the solution of possibly not well‐posed ...
R. J. Villanueva, L. Jodar
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Stable matrices, the Cayley transform, and convergent matrices
International Journal of Mathematics and Mathematical Sciences, Volume 14, Issue 1, Page 77-81, 1991., 1991 The main result is that a square matrix D is convergent () if and only if it is the Cayley transform CA = (I − A) −1(I + A) of a stable matrix A, where a stable matrix is one whose characteristic values all have negative real parts. In passing, the concept of Cayley transform is generalized, and the generalized version is shown closely related to the ...
Tyler Haynes
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