Towards a proof of Euler's polyhedron formula for Mathlib
Euler's polyhedron formula is the mathematical result that polyhedra satisfy the equation V + E - F = 2. I'm working on adding this to Lean's Mathlib.
Articles
Notes on AI for Mathematics and Theoretical Computer Science
I attended an amazing workshop on the impacts of AI on mathematical research at the Simons Institute for the Theory of Computing at UC Berkeley; my thoughts.
Leaning In! 2025 from the organizer's point of view
Leaning In! 2025 was a one-day get-together for the Lean community in and around Berlin, Germany. Here's how it went.
Announcing Leaning In! 2025, a workshop for Lean enthusiasts
Leaning In! is an in-person workshop for enthusiasts of the Lean proof assistant. The next edition will be held on Thursday, March 13th, 2025 in Berlin.
Announcing a polyfill for the TC39 decimal proposal
A new NPM package tracking the TC39 decimal proposal is now available. ESM and all-in-one bundled variants are available.
Getting started with Lean 4, your next programming language
Lean is a language that supports proving while programming. Here's what I found when I first dived in, with a couple of gotchas.
The decimals around us: Cataloging support for decimal numbers
Many programming languages have support for decimals in various forms. Here is a catalog of where they stand regarding their support for decimals.
Native support for decimal numbers in the Python programming language
The Python programming langauge supports decimal numbers in its standard library. Here's a summary of how to work with this important data type.
Announcing decimal128: JavaScript implementation of Decimal128
I've made an NPM package that allows you to work with IEEE 754 Decimal128 values in your JavaScript programs. Time to start working with decimal numbers!
Binary floats can let us down! When close enough isn't enough
Standard IEEE-754 binary floating point numbers can let us down, even on simple calcualtions. Or: is your bill correct?
Use case for decimals in JavaScript
Would it be useful to add support for decimal numbers to JavaScript? Here are some uses known use cases.
Racketfest, the little Racket conference that could, is back!
Racketfest is a festival for Racket enthusiasts based in or near Europe. The next edition will be held on Saturday, March 18, 2023 in Berlin, Germany.
A comprehensive, authoritative FAQ on decimal arithmetic
Mike Cowlishaw, editor of the 2008 edition of the IEEE 754 floating-point arithmetic standard, has a delightful FAQ page on decimal arithmetic.
QuickJS already supports arbitrary-precision decimals
QuickJS is a JavaScript engine that supports arbitrary-precision decimals. Here's how to play around with them.
Here's how to unbreak floating-point math in JavaScript
Just discover that 0.1 + 0.2 isn't 0.3 in JavaScript? WTF? What's wrong? Can anything be done? Yes! (Though it may take some time.)