8 papers · 1 filter
Randomized Tucker-Sketched GMRES
Alberto Bucci, Martina Iannacito, Mirjeta Pasha +1
We address the problem of solving large-scale tensor-structured linear systems in the Tucker format. In this setting, standard iterative solvers such as GMRES face a fundamental bo…
An Equivalence result for sketched Anderson Acceleration and sketched GMRES
Alberto Bucci, Fabio Durastante
In this paper we present an equivalence result between a randomized version of Anderson Acceleration and of randomized GMRES for linear problems. Namely, we extend the classical re…
Randomized Flexible LSQR and LSMR with applications to inverse problems
Alberto Bucci, Silvia Gazzola, Leonardo Robol
LSQR and LSMR are iterative methods, based on the Golub-Kahan bidiagonalization algorithm, widely used for large-scale linear least squares problems. FLSQR and FLSMR are flexible v…
Numerical Stability of the Nyström Method
Alberto Bucci, Yuji Nakatsukasa, Taejun Park
The Nyström method is a widely used technique for improving the scalability of kernel-based algorithms, including kernel ridge regression, spectral clustering, and Gaussian proces…
Randomized algorithms for streaming low-rank approximation in tree tensor network format
Alberto Bucci, Gianfranco Verzella
In this work, we present the tree tensor network Nyström (TTNN), an algorithm that extends recent research on streamable tensor approximation, such as for Tucker and tensor-train…
Randomized sketched TT-GMRES for linear systems with tensor structure
Alberto Bucci, Davide Palitta, Leonardo Robol
In the last decade, tensors have shown their potential as valuable tools for various tasks in numerical linear algebra. While most of the research has been focusing on how to compr…