Nick Trethen is a world famous computational scientist and my good friend.

Contents

Serra House

I first met Nick in 1978 at Stanford's Serra House. Serra House was built in 1923 to be the retirement home for President David Starr Jordan. By the late 1970's it had been assigned to the Computer Science Department and housed the Numerical Analysis group. Professors George Forsythe and Gene Golub had their offices there at one time or another, as did various grad students, post docs, and visitors.

There was a lovely patio, a volleyball court and a real feeling of camaraderie in the Serra House group. In the academic year 1978/79 a particularly strong group of grad studies were working in Serra House. Nick Trefethen was one of them. Marsha Berger, Michael Overton and Randy LeVeque were others.

In 1978/79 Gene Golub was away from Stanford on sabbatical and I took his place for the year. I taught the graduate numerical analysis course and used my new Fortran "matrix laboratory". It was just a primitive matrix calculator. It was not impressive numerical analysis nor impressive computer science.

Nick and Randy were enrolled in that course and Marsha and Michael sat in sometimes. This was their first exposure to MATLAB. It would have to become a more mature tool before they would find it useful. A few grad students from engineering also took my course and found that primitive MATLAB useful for work in areas like control theory and signal processing, areas that I knew nothing about at the time. That eventually led to Jack Little and to MathWorks.

Nick

Chebfun

https://blogs.mathworks.com/cleve/wp-admin/options-permalink.php

https://www.henkvandervorst.nl/computing.html

Linocut by Henk van der Vorst.

Nick is a renowned scholar of computational mathematics. His curriculum vitae provides a list of his achievements. He has authored eight books, published hundreds of journal articles and written dozens of essays, He is a fellow of the US National Academy of Engineering and the British Royal Society. He served as president of SIAM and as editor and associate editor for a number of journals.

Here is a sample of a few of his achievements.

Academic Career

Nick received his Stanford Ph.D.in 1982. His thesis supervisor was Joe Oliger. From 1982 to 1997 he was on the faculty of NYU, MIT and Cornell.

In 1997, he moved to Oxford University to succeed Leslie Fox as Professor of Numerical Analysis and Fellow of Balliol College. Nick's essay An American at Oxford is fascinating.

Wilkinson

Nick gave this talk about Jim Wilkinson in 1979.

https://www.youtube.com/watch?v=kOMrRn2tdCs

60th Birthday

A conference for Nick's birthday as held in 2015 in Oxford's new Andrew Wiles Building. That's Andre Weideman in the front row with Nick and me.

https://blogs.mathworks.com/cleve/2015/09/07/trip-report-trefethen-birthday-conference

Chebfun

Chebfun is a powerful system for dealing with functions and operators in the same way MATLAB deals with vectors and matrices. The web site: https://www.chebfun.org.

The logo:

The original authors, Nick, Toby Driscoll, Ricardo Pachón and Rodrigo Platte:

100 Digits

In 2002, Nick specified ten problems, each with a numerical solution. He offered a $100 prize to whoever produced the most accurate solutions, measured up to ten significant digits. Ultimately twenty teams solved all of the problems perfectly. An anonymous donor aided in producing the required prize money. The challenge and its solutions were described in detail by Folkmar Bornemann, Dirk Laurie, Stan Wagon and Jörg Waldvogel in

The SIAM 100-Digit Challenge.

One of the problems is to find the global minimum of

f = @(x,y) exp(sin(50*x)) + sin(60*exp(y)) + sin(70*sin(x)) + sin(sin(80*y)) - sin(10*(x+y)) + (x.^2+y.^2)./4;

Here is a surf plot of f(x,y).

Lightning Laplace Solver

The Lightning Laplace Solver is a MATLAB code that solves the Laplace equation on a polygon.

https://people.maths.ox.ac.uk/trefethen/lightning.html

AAA

AAA is a new algorithm for rational approximation. The name AAA stands for “adaptive Antoulas-Anderson” in honor of the authors who introduced the idea.

https://people.maths.ox.ac.uk/trefethen/AAAfinal.pdf

Body-Mass Index

In 2013 Nick wrote this one-page note proposing an alternative to the standard Body-Mass Index, which is widely used to assess obesity.

https://people.maths.ox.ac.uk/trefethen/bmi.pdf

Index Cards

Nick writes:

For many years, since 1970 in fact, I have been writing notes on social, mathematical, and other subjects, which I store on index cards. A collection of several hundred of these notes was published ... as Trefethen’s Index Cards: Forty Years of Notes about People, Words and Mathematics (World Scientific, 2011).

See: https://trefethen.net

Harvard

In 2023, Nick returned to Harvard, where he had been an undergraduate fifty years earlier. (Bill Gates was in the same class.) This time around, Nick is Professor of Applied Mathematics in Residence at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS). The announcement: Trefethen Returns to Harvard.

Get the MATLAB code

Published with MATLAB® R2024b