Jörn Zimmerling

activity

20242026

collaborators

3 papers

math.NA2026

Adapting the Lanczos algorithm to matrices with almost continuous spectra

Jörn Zimmerling, Vladimir Druskin

We consider approximating $B^{T} (A + s I)^{- 1} B$ , where $A \in R^{n \times n}$ is large, symmetric positive definite, and $B \in R^{n \times p}$ with $p ≪ n$ . We focus on t…

math.NA2025

A Krylov projection algorithm for large symmetric matrices with dense spectra

Vladimir Druskin, Jörn Zimmerling

We consider the approximation of $B^{T} (A + s I)^{- 1} B$ for large s.p.d. $A \in R^{n \times n}$ with dense spectrum and $B \in R^{n \times p}$ , $p ≪ n$ . We target the com…

math.NA2024

Monotonicity, bounds and extrapolation of Block-Gauss and Gauss-Radau quadrature for computing $B^{T} ϕ (A) B$

Jörn Zimmerling, Vladimir Druskin, Valeria Simoncini

In this paper, we explore quadratures for the evaluation of $B^{T} ϕ (A) B$ where $A$ is a symmetric positive-definite (s.p.d.) matrix in $R^{n \times n}$ , $B$ is a tall matr…

Adapting the Lanczos algorithm to matrices with almost continuous spectra

A Krylov projection algorithm for large symmetric matrices with dense spectra

Monotonicity, bounds and extrapolation of Block-Gauss and Gauss-Radau quadrature for computing BTϕ(A)B

Monotonicity, bounds and extrapolation of Block-Gauss and Gauss-Radau quadrature for computing $B^{T} ϕ (A) B$