Nikos Barakitis

collaborators

2 papers

math.NA2025

Blocking structures, approximation, and preconditioning

Nikos Barakitis, Marco Donatelli, Samuele Ferri +3

We consider block-structured matrices $A_{n}$ , where the blocks are of (block) unilevel Toeplitz type with $s \times t$ matrix-valued generating functions. Under mild assumptions on t…

math.NA2024

A note on eigenvalues and singular values of variable Toeplitz matrices and matrix-sequences, with application to variable two-step BDF approximations to parabolic equations

Nikos Barakitis, Valerio Loi, Stefano Serra-Capizzano

Here, we consider a more general class of matrix-sequences and we prove that they belong to the maximal $*$ -algebra of generalized locally Toeplitz (GLT) matrix-sequences. Then, we…