Author Archives: Brent

About Brent

Assistant Professor of Computer Science at Hendrix College. Functional programmer, mathematician, teacher, pianist, follower of Jesus.

Parametricity for Bifunctor

Posted on March 30, 2018

I’ve begun work to add Bifunctor, Bifoldable, and Bitraversable to the Typeclassopedia. While thinking and writing about Bifunctor I ended up proving some “folklore” results for my own satisfaction, and decided someone might possibly find it useful if I formally … Continue reading →

Posted in haskell, math | Tagged , , , , , | 2 Comments

Beeminder guest post on Beeminding All The Things

Posted on March 5, 2018

I’ve written about my use of Beeminder a few times here before. I just wrote a guest post for the Beeminder blog entitled Beeminding All The Things, in which I explain some lessons learned and best practices for dealing with … Continue reading →

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Test your intuition: logarithmic time

Posted on February 28, 2018

Here is a question to test your intuition for logarithms. NO CALCULATORS allowed, and don’t take a long time to work out an answer in your head! Just go with your gut. After you have committed to a choice (say, … Continue reading →

Posted in teaching | Tagged , , , | 11 Comments

Visiting assistant professor position at Hendrix

Posted on February 24, 2018

My department at Hendrix College is hiring a 1-year visitor in CS for next year. This is my third year at Hendrix and I really love it—the department is friendly and supportive, the administration really cares about faculty and students, … Continue reading →

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A (work in progress) translation of Joyal’s original paper on species

Posted on February 13, 2018

tl;dr: I’m working on an English translation, with additional commentary, of Joyal’s 1981 paper introducing the concept of combinatorial species. Collaboration and feedback welcome! Back when I was writing my PhD thesis on combinatorial species, I was aware that André … Continue reading →

Posted in combinatorics, projects, species, writing | Tagged , , , , , , | 4 Comments

Off the Beaten Track: Explaining Type Errors

Posted on January 21, 2018

Last week I gave a talk at Off the Beaten Track 2018 about something that Richard Eisenberg, Harley Eades and I have been thinking about recently: namely, how to generate good interactive error explanations for programmers, especially for type errors. … Continue reading →

Posted in projects, writing | Tagged , , , , , , , , | 2 Comments

Sum of heights in a binary tree

Posted on November 3, 2017

Executive summary: every year when teaching data structures I always forget how to analyze the cost of building a binary heap, which amounts to summing the heights of all the nodes in a full binary tree. So I’m writing down … Continue reading →

Posted in math, teaching | Tagged , , , , , , , | 1 Comment