New results about semi-positive matrices

Jonathan Dorsey; Tom Gannon; Charles R. Johnson; Morrison Turnansky

Displaying similar documents to “New results about semi-positive matrices”

A sparsity result on nonnegative real matrices with given spectrum

Thomas Laffey (1997)

Banach Center Publications

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Let σ=(λ1,...,λn) be the spectrum of a nonnegative real n × n matrix. It is shown that σ is the spectrum of a nonnegative real n × n matrix having at most ${(n + 1)}^{2} / 2 - 1$ nonzero entries.

Nearly principal minors of $M$ -matrices

Gerard Sierksma, Evert Jan Bakker (1986)

Compositio Mathematica

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Nonsingularity and $P$ -matrices.

Jiří Rohn (1990)

Aplikace matematiky

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New proofs of two previously published theorems relating nonsingularity of interval matrices to $P$ -matrices are given.

On block triangular matrices with signed Drazin inverse

Changjiang Bu, Wenzhe Wang, Jiang Zhou, Lizhu Sun (2014)

Czechoslovak Mathematical Journal

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The sign pattern of a real matrix $A$ , denoted by $sgn A$ , is the $(+, -, 0)$ -matrix obtained from $A$ by replacing each entry by its sign. Let $𝒬 (A)$ denote the set of all real matrices $B$ such that $sgn B = sgn A$ . For a square real matrix $A$ , the Drazin inverse of $A$ is the unique real matrix $X$ such that $A^{k + 1} X = A^{k}$ , $X A X = X$ and $A X = X A$ , where $k$ is the Drazin index of $A$ . We say that $A$ has signed Drazin inverse if $sgn {\tilde{A}}^{d} = sgn A^{d}$ for any $\tilde{A} \in 𝒬 (A)$ , where $A^{d}$ denotes the Drazin inverse of $A$ . In this paper, we give necessary conditions for some block triangular matrices...

The Re-nonnegative definite solutions to the matrix equation $A X B = C$

Qing Wen Wang, Chang Lan Yang (1998)

Commentationes Mathematicae Universitatis Carolinae

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An $n \times n$ complex matrix $A$ is called Re-nonnegative definite (Re-nnd) if the real part of $x^{*} A x$ is nonnegative for every complex $n$ -vector $x$ . In this paper criteria for a partitioned matrix to be Re-nnd are given. A necessary and sufficient condition for the existence of and an expression for the Re-nnd solutions of the matrix equation $A X B = C$ are presented.

Displaying similar documents to “New results about semi-positive matrices”

A sparsity result on nonnegative real matrices with given spectrum

Nearly principal minors of M -matrices

Nonsingularity and P -matrices.

On block triangular matrices with signed Drazin inverse

The Re-nonnegative definite solutions to the matrix equation A X B = C

Nearly principal minors of $M$ -matrices

Nonsingularity and $P$ -matrices.

The Re-nonnegative definite solutions to the matrix equation $A X B = C$