activity
20122026
most citedThe automatic solution of partial differential equations using a global spectral method

73 citations · 398 across the 44 of their papers we have counts for

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Showing 2023Show all

5 papers · 1 filter

math.DS2023

Beyond expectations: Residual Dynamic Mode Decomposition and Variance for Stochastic Dynamical Systems

Matthew J. Colbrook, Qin Li, Ryan V. Raut +1

Koopman operators linearize nonlinear dynamical systems, making their spectral information of crucial interest. Numerous algorithms have been developed to approximate these spectra…

math.NA2023

Avoiding discretization issues for nonlinear eigenvalue problems

Matthew J. Colbrook, Alex Townsend

The first step when solving an infinite-dimensional eigenvalue problem is often to discretize it. We show that one must be extremely careful when discretizing nonlinear eigenvalue…

math.NA2023★ 1 cited

Leveraging the Hankel norm approximation and block-AAA algorithms in reduced order modeling

Annan Yu, Alex Townsend

Large-scale linear, time-invariant (LTI) dynamical systems are widely used to characterize complicated physical phenomena. We propose a two-stage algorithm to reduce the order of a…

cs.LG2023★ 17 cited

Elliptic PDE learning is provably data-efficient

Nicolas Boullé, Diana Halikias, Alex Townsend

PDE learning is an emerging field that combines physics and machine learning to recover unknown physical systems from experimental data. While deep learning models traditionally re…

math.NA2023

Are sketch-and-precondition least squares solvers numerically stable?

Maike Meier, Yuji Nakatsukasa, Alex Townsend +1

Sketch-and-precondition techniques are efficient and popular for solving large least squares (LS) problems of the form with and . This i…