Category Archives: haskell

BlogLiterately 0.8.1, now with HTTPS!

I’ve just released version 0.8.1 of BlogLiterately, a tool for formatting and posting stuff (especially Haskelly stuff) to blogs. This is in conjunction with the release of haxr-3000.11. After much blood, sweat, and tears, I was able to rip the … Continue reading

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Pan-Galactic Division in Haskell

Summary: given an injective function , it is possible to constructively “divide by ” to obtain an injection , as shown recently by Peter Doyle and Cecil Qiu and expounded by Richard Schwartz. Their algorithm is nontrivial to come up … Continue reading

Posted in haskell, math, species | Tagged , , , , , , , , , | 6 Comments

Diagrams 1.0

The diagrams team is very pleased to announce the 1.0 release of diagrams, a framework and embedded domain-specific language for declarative drawing in Haskell. Check out the gallery for some examples of what it can do. Diagrams can be used … Continue reading

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Catsters guide

tl;dr: In an attempt to solidify and extend my knowledge of category theory, I have been working my way through the excellent series of category theory lectures posted on Youtube by Eugenia Cheng and Simon Willerton, aka the Catsters. … Continue reading

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

Come visit the FARM!

Registration is now open for the first (!) ACM SIGPLAN Workshop on Functional Art, Music, Modeling and Design (FARM), to be held in Boston on September 28 (the day after ICFP). I’m really excited—it’s shaping up to be a really … Continue reading

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Monad transformers: a cautionary tale

When writing the code in my previous post, I wanted to have a monad which combined the ability to generate random numbers with the ability to fail. Naturally, I decided to use RandT Maybe. But when I tried to write … Continue reading

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Random binary trees with a size-limited critical Boltzmann sampler

Today I’d like to talk about generating random trees. First, some imports and such (this post is literate Haskell). > {-# LANGUAGE GeneralizedNewtypeDeriving #-} > > module BoltzmannTrees where > > import Control.Applicative > import Control.Arrow ((&&&)) > import Control.Lens … Continue reading

Posted in combinatorics, haskell, math, species | Tagged , , , , , | 13 Comments