8 papers · 1 filter
Fast stability tests for Hermitian matrix polynomials
Vanni Noferini, Xuzhou Zhan
Assessing the asymptotic stability of linear self-adjoint homogeneous systems of differential-algebraic equations requires testing the Hurwitz stability of the associated Hermitian…
Nearest matrix with multiple eigenvalues by Riemannian optimization
Vanni Noferini, Lauri Nyman, Federico Poloni
Given a square complex matrix , we tackle the problem of finding the nearest matrix with multiple eigenvalues or, equivalently when had distinct eigenvalues, the nearest def…
Riemann-Oracle: A general-purpose Riemannian optimizer to solve nearness problems in matrix theory
Miryam Gnazzo, Vanni Noferini, Lauri Nyman +1
We propose an extremely versatile approach to address a large family of matrix nearness problems, possibly with additional linear constraints. Our method is based on splitting a ma…
On rank-2 Nonnegative Matrix Factorizations and their variants
Etna Lindy, Vanni Noferini, Paul Van Dooren
We consider the problem of finding the best nonnegative rank-2 approximation of an arbitrary nonnegative matrix. We first revisit the theory, including an explicit parametrization…
Finding the nearest -stable pencil with Riemannian optimization
Vanni Noferini, Lauri Nyman
This paper considers the problem of finding the nearest -stable pencil to a given square pencil , where a pencil is called -stable if it i…
Efficient computation of \lowercase{}-centralities and nonbacktracking centrality for temporal networks
Vanni Noferini, Spyridon Vrontos, Ryan Wood
We discuss efficient computation of -centralities and nonbacktracking centralities for time-evolving networks with nonnegative weights. We present a node-level formula for its c…