1 citations · 1 across the 8 of their papers we have counts for
Showing 2026Show all
3 papers · 1 filter
math.NA2026
Sketch-and-Restart: Randomized Sketching in Quadrature-Based Restarting for Matrix Functions
Stefan Güttel, Jingyu Liu, Lauri Nyman
We develop a sketch-and-restart framework for computing the action of a matrix function on a vector, , where is large, sparse, and non-Hermitian. The framework combines…
math.NA2026
Flexible GMRES converges in two phases
Stefan Güttel, Lauri Nyman
We derive a sharp upper bound on the residuals produced by the flexible GMRES (FGMRES) method. The bound shows that FGMRES exhibits two phases of convergence depending on the resid…
math.NA2026
Singular vector spaces for computing the structured distance to singularity
Lauri Nyman
Finding the distance to singularity for a matrix is a ubiquitous problem in numerical linear algebra, and is elegantly solved by the Eckart-Young-Mirsky theorem. Its structured var…