Special Matrices (Sep 2023)

Combined matrix of diagonally equipotent matrices

  • Bru Rafael,
  • Gassó Maria T.,
  • Giménez Isabel,
  • Santana Máximo,
  • Scott José

DOI
https://doi.org/10.1515/spma-2023-0101
Journal volume & issue
Vol. 11, no. 1
pp. 144 – 151

Abstract

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Let C(A)=A∘A−T{\mathcal{C}}\left(A)=A\circ {A}^{-T} be the combined matrix of an invertible matrix AA, where ∘\circ means the Hadamard product of matrices. In this work, we study the combined matrix of a nonsingular matrix, which is an HH-matrix whose comparison matrix is singular. In particular, we focus on C(A){\mathcal{C}}\left(A) when AA is diagonally equipotent, and we study whether C(A){\mathcal{C}}\left(A) is an HH-matrix and to which class it belongs. Moreover, we give some properties on the diagonal dominance of these matrices and on their comparison matrices.

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