Evert Provoost

Numerical Analyst, PhD

About me

I recently obtained a PhD at the NUMA research unit of KU Leuven’s Department of Computer Science. I worked on ‘The Lanczos Tau Method for Time-Delay Systems’ under the supervision of Wim Michiels.

My research focuses on developing numerical methods for infinite-dimensional dynamical systems, particularly those governed by delay and functional differential equations. I work at the intersection of approximation theory, numerical analysis, and dynamical systems theory, with an increasing interest in computational methods for nonlinear dynamics, including the numerical discovery of attractors and the corresponding basins of attraction of infinite-dimensional systems. Whilst my work primarily involves theoretical and computational aspects of these methods, the questions and problems they aim to solve are inspired by applications in engineering and the life sciences.

If you want to know more about my research, or for any other professional or personal inquiries, you can always contact me via email or XMPP on ‘my first name’@eprovst.net.

Works

Below is a list of my scientific output with links to preprints and slides. You can find my full CV here.

Publications and preprints

Talks and seminars

Basins of attraction of FDEs

Lanczos tau methods for DD(A)Es

Domain colouring

Somewhat loosely related to my scientific activities I also ended up getting intrigued by domain colouring, a way to visualize complex functions. This resulted in the development of the Julia packages Domain­Coloring.jl and Complex­Toys.jl. Of note in the method used in these packages is the use of an analytical sweep through the Oklab colour space, resulting in far fewer artefacts and false representations than the usual HSV hue sweep.

The figure shows the fifth diagonal Padé approximant of e−s as appears in the transfer function when approximating a time-delay system using a Lanczos tau method truncating in the Legendre basis.