Matrices diagonally similar to a symmetric matrix

Matrices Diagonally Similar to a Symmetric Matrix

Let IF be field, and let A and B be n X n matrices with elements in IF. Suppose that A is completely reducible and that B is symmetric. If the principal minors of A determined by the 1and 2-circuits of the graph of B and by the chordless circuits of the graph of A are equal to the corresponding principal minors of B, then A is diagonally similar to B; and conversely.

Diagonally and Antidiagonally Symmetric Alternating Sign Matrices of Odd Order

We study the enumeration of diagonally and antidiagonally symmetric alternating sign matrices (DASASMs) of fixed odd order by introducing a case of the six-vertex model whose configurations are in bijection with such matrices. The model involves a grid graph on a triangle, with bulk and boundary weights which satisfy the Yang–Baxter and reflection equations. We obtain a general expression for t...

Inverses of symmetric, diagonally dominant positive matrices and applications

We prove tight bounds for the ∞-norm of the inverse of a symmetric, diagonally dominant positive matrix J ; in particular, we show that ‖J‖∞ is uniquely maximized among all such J . We also prove a new lower-bound form of Hadamard’s inequality for the determinant of diagonally dominant positive matrices and an improved upper bound for diagonally balanced positive matrices. Applications of our r...

Doubly Diagonally Dominant Matrices

We consider the class of doubly diagonally dominant matrices (A = [ ajj] E C”, ‘, la,,1 l”jjl > Ck+ i laiklCk+ jlajkl. i #j) and its subclasses. We give necessary and sufficient conditions in terms of the directed graph for an irreducibly doubly diagonally dominant matrix to be a singular matrix or to be an H-matrix. As in the case of diagonal dominance, we show that the Schur complements of do...

A note on nonnegative diagonally dominant matrices