Uploaded November 2022 | Updated September 2026, 2 weeks ago
We have seen that the error of numerical differentiation typically scales with the time step dt. So why can't we just reduce the time step arbitrarily small to control the error? This video describes how numbers are stored in a computer and how small roundoff errors are amplified by very small dt's, giving a lower limit to how small we can make our time steps.
Playlist: youtube.com/playlist?list=PLMrJAkhIeNNTYaOnVI3QpH7jgULnAmvPA
Course Website: http://faculty.washington.edu/sbrunton/me564/
@eigensteve on Twitter
eigensteve.com
databookuw.com
This video was produced at the University of Washington
%%% CHAPTERS %%%
0:00 Numerical roundoff error: How numbers are stored in a computer
8:40 Two sources of error: Roundoff and Taylor series
We have seen that the error of numerical differentiation typically scales with the time step dt. So why can't we just reduce the time step arbitrarily small to control the error? This video describes how numbers are stored in a computer and how small roundoff errors are amplified by very small dt's, giving a lower limit to how small we can make our time steps.
Playlist: youtube.com/playlist?list=PLMrJAkhIeNNTYaOnVI3QpH7jgULnAmvPA
Course Website: http://faculty.washington.edu/sbrunton/me564/
@eigensteve on Twitter
eigensteve.com
databookuw.com
This video was produced at the University of Washington
%%% CHAPTERS %%%
0:00 Numerical roundoff error: How numbers are stored in a computer
8:40 Two sources of error: Roundoff and Taylor series
![Fourier Neural Operator (FNO) [Physics Informed Machine Learning]
This video was produced at the University of Washington, and we acknowledge funding support from the Boeing Company
%%% CHAPTERS %%%
00:00 Intro
01:54 Operators as Images, Fourier as Convolution
04:43 Zero-Shot Super Resolution
07:33 Generalizing Neural Operators
09:47 Conditions and Operator Kernels
10:53 Mesh Invariance
12:31 Why Neural Operators // Or Neural operators vs other methods
13:47 Result: Greens Function
15:14 Laplace Neural Operators
17:14 Outro Fourier Neural Operator (FNO) [Physics Informed Machine Learning]](https://i.ytimg.com/vi/W8PybqAk6Ik/mqdefault.jpg)








![Measure-preserving EDMD: A 4-line structure-preserving & convergent DMD algorithm!
Research Abstract by Matt Colbrook, Cambridge University
We introduce measure-preserving extended dynamic mode decomposition (mpEDMD), a data-driven algorithm that enforces measure-preserving truncations of Koopman operators using a general dictionary of observables. It is flexible and easy to use with any pre-existing DMD-type method and with different data types. As well as convergence to the spectral properties of the underlying Koopman operator (for general measure-preserving dynamical systems), mpEDMD has improved stability and qualitative behavior of trajectories. For delay embedding, mpEDMD even comes with explicit convergence rates as the size of the dictionary increases. We demonstrate mpEDMD on a range of challenging examples, its increased robustness to noise compared with other DMD-type methods, and its ability to capture the energy conservation and statistics of a turbulent boundary layer flow with Reynolds number greater than 60,000 and state-space dimension greater than 100,000.
http://www.damtp.cam.ac.uk/user/mjc249/pdfs/mpEDMD.pdf [damtp.cam.ac.uk] Measure-preserving EDMD: A 4-line structure-preserving & convergent DMD algorithm!](https://i.ytimg.com/vi/Xt3vS_hhBm8/mqdefault.jpg)
