Helena vSmigoc

activity

20162021

most citedDiagonal elements in the Nonnegative Inverse Eigenvalue Problem

3 citations · 6 across the 4 of their papers we have counts for

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math.SP2019

The integer cp-rank of $2 \times 2$ matrices

Thomas Laffey, Helena Šmigoc

We show the cp-rank of an integer doubly nonnegative $2 \times 2$ matrix does not exceed $11$ .

math.SP2018

Diagonal realizability in the Nonnegative Inverse Eigenvalue Problem

Thomas J. Laffey, Helena Šmigoc

We show that if a list of nonzero complex numbers $σ = (λ_{1}, λ_{2}, \dots, λ_{k})$ is the nonzero spectrum of a diagonalizable nonnegative matrix, then $σ$ is the nonzero spectrum of a dia…

math.SP2017★ 3 cited

Diagonal elements in the Nonnegative Inverse Eigenvalue Problem

Richard Ellard, Helena Šmigoc

We say that a list of complex numbers is "realisable" if it is the spectrum of some (entrywise) nonnegative matrix. The Nonnegative Inverse Eigenvalue Problem (NIEP) is the problem…

math.SP2016

The maximum of the minimal multiplicity of eigenvalues of symmetric matrices whose pattern is constrained by a graph

Polona Oblak, Helena Šmigoc

In this paper we introduce a parameter $M m (G)$ , defined as the maximum over the minimal multiplicities of eigenvalues among all symmetric matrices corresponding to a graph $G$ . We…

The integer cp-rank of 2×2 matrices

Diagonal realizability in the Nonnegative Inverse Eigenvalue Problem

Diagonal elements in the Nonnegative Inverse Eigenvalue Problem

The maximum of the minimal multiplicity of eigenvalues of symmetric matrices whose pattern is constrained by a graph

The integer cp-rank of $2 \times 2$ matrices