collaborators

5 papers

math.NA2025

Spectral equivalence of unsymmetric kernel matrices and applications

Tizian Wenzel, Armin Iske

Symmetric kernel matrices are a well-researched topic in the literature of kernel based approximation. In particular stability properties in terms of lower bounds on the smallest e…

math.FA2025

Inducing Riesz and orthonormal bases in via composition operators

Yahya Saleh, Armin Iske

Let be a composition operator mapping into for some open sets . We characterize the mappings that transform Rie…

math.NA2025

Spectral alignment of kernel matrices and applications

Tizan Wenzel, Armin Iske

Kernel matrices are a key quantity in kernel-based approximation, and important properties such as stability and algorithmic convergence can be analyzed with their help. In this wo…

math.NA2024

Product kernels are efficient and flexible tools for high-dimensional scattered data interpolation

Kristof Albrecht, Juliane Entzian, Armin Iske

This work concerns the construction and characterization of product kernels for multivariate approximation from a finite set of discrete samples. To this end, we consider composing…

math.NA2024

On the convergence of generalized kernel-based interpolation by greedy data selection algorithms

Kristof Albrecht, Armin Iske

We analyze the convergence of generalized kernel-based interpolation methods. This is done under minimalistic assumptions on both the kernel and the target function. On these groun…