Author Archives: Brent

About Brent

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

Worstsort

Thanks for the responses to my previous post about finding roots of polynomials; I now have some new avenues to explore. But today I want to write about something completely different. I recently stumbled across this fun paper by Miguel … Continue reading

Posted in haskell, humor, math | Tagged , , , , , | 8 Comments

Finding roots of polynomials in Haskell?

tl;dr: There are several Haskell packages one can use to find an individual root of a function on a certain interval. But I’ve had less luck finding a suitable package for finding all the roots of a given polynomial. This … Continue reading

Posted in haskell, math | Tagged , , , , , | 14 Comments

Hendrix teams at ACM ICPC

Today I took five students from Hendrix to Fort Smith to compete in the Mid-Central USA Regional of the ACM International Collegiate Programming Contest (ICPC). Both teams solved five out of ten problems, and finished second and fourth out of … Continue reading

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

What’s the Difference? video and slides

At ICFP in St. Louis I presented my paper with Kenny Foner, What’s the Difference? A Functional Pearl on Subtracting Bijections. Many people seemed to enjoy the talk and we got lots of great feedback afterwards. We will probably write up … Continue reading

Posted in combinatorics, haskell, writing | Tagged , , , , , , | 2 Comments

Counting inversions with monoidal sparks

Time for me to reveal the example I had in mind that led to the generalization in my previous post. Thanks for all the interesting comments: it seems like there are some interesting connections to be explored (e.g. to the … Continue reading

Posted in math | Tagged , , , , , , , , | 7 Comments

Monoidal sparks

While at ICFP in St. Louis this past week, I discovered an interesting construction on monoids that no one I talked to (including Kenny Foner and Edward Kmett) seemed to have heard of or thought about before. In this post I’ll … Continue reading

Posted in math | Tagged , , , , | 27 Comments

New ICFP functional pearl on subtracting bijections

Kenny Foner and I have a paper accepted to ICFP on subtracting bijections. Here’s the basic problem: suppose you have a bijection between two sum types, , and another bijection . Of course and must have the same size, but … Continue reading

Posted in combinatorics, haskell, writing | Tagged , , , , , | 5 Comments