activity
20182022
collaborators

16 papers

math.OC2022

Solving matrix nearness problems via Hamiltonian systems, matrix factorization, and optimization

Nicolas Gillis, Punit Sharma

In these lectures notes, we review our recent works addressing various problems of finding the nearest stable system to an unstable one. After the introduction, we provide some pre…

eess.SP2020

Successive Nonnegative Projection Algorithm for Linear Quadratic Mixtures

Christophe Kervazo, Nicolas Gillis, Nicolas Dobigeon

In this work, we tackle the problem of hyperspectral (HS) unmixing by departing from the usual linear model and focusing on a Linear-Quadratic (LQ) one. The proposed algorithm, ref…

cs.LG2020

Sparse Separable Nonnegative Matrix Factorization

Nicolas Nadisic, Arnaud Vandaele, Jeremy E. Cohen +1

We propose a new variant of nonnegative matrix factorization (NMF), combining separability and sparsity assumptions. Separability requires that the columns of the first NMF factor…

cs.LG2020

On a minimum enclosing ball of a collection of linear subspaces

Timothy Marrinan, P. -A. Absil, Nicolas Gillis

This paper concerns the minimax center of a collection of linear subspaces. When the subspaces are -dimensional subspaces of , this can be cast as finding the cent…

math.NA2020

Off-diagonal Symmetric Nonnegative Matrix Factorization

François Moutier, Arnaud Vandaele, Nicolas Gillis

Symmetric nonnegative matrix factorization (symNMF) is a variant of nonnegative matrix factorization (NMF) that allows to handle symmetric input matrices and has been shown to be p…

math.OC2020

A block inertial Bregman proximal algorithm for nonsmooth nonconvex problems with application to symmetric nonnegative matrix tri-factorization

Masoud Ahookhosh, Le Thi Khanh Hien, Nicolas Gillis +1

We propose BIBPA, a block inertial Bregman proximal algorithm for minimizing the sum of a block relatively smooth function (that is, relatively smooth concerning each block) and bl…