collaborators

7 papers

math.NA2026

Optimal near-optimality bounds for the Lanczos method for matrix functions

Tyler Chen, David Persson

Let be Hermitian positive definite and let denote the Lanczos approximation to . We prove that if or is Stieltjes, then the -norm error of t…

math.NA2026

A recursive butterfly factorization with optimality guarantees

David Persson, Paul G. Beckman, Tyler Chen +2

We formalize a recursive format for representing a butterfly matrix. This new format naturally leads to a simple recursive algorithm for computing a quasi-optimal butterfly approxi…

math.NA2026

Linear Systems and Eigenvalue Problems: Open Questions from a Simons Workshop

Noah Amsel, Yves Baumann, Paul Beckman +36

This document presents a series of open questions arising in matrix computations, i.e., the numerical solution of linear algebra problems. It is a result of working groups at the w…

math.NA2025

Randomized block-Krylov subspace methods for low-rank approximation of matrix functions

David Persson, Tyler Chen, Christopher Musco

The randomized SVD is a method to compute an inexpensive, yet accurate, low-rank approximation of a matrix. The algorithm assumes access to the matrix through matrix-vector product…

cs.DS2025

Does block size matter in randomized block Krylov low-rank approximation?

Tyler Chen, Ethan N. Epperly, Raphael A. Meyer +2

We study the problem of computing a rank- approximation of a matrix using randomized block Krylov iteration. Prior work has shown that, for block size or , a $(1…

math.NA2025

Quasi-optimal hierarchically semi-separable matrix approximation

Noah Amsel, Tyler Chen, Feyza Duman Keles +4

We present a randomized algorithm for producing a quasi-optimal hierarchically semi-separable (HSS) approximation to an matrix using only matrix-vector products wit…