Brandon Simmons' website

In Data.Array the function array :: (IArray a e, Ix i) => (i, i) -> [(i, e)] -> a i e takes the array bounds and an association list, and it produces an Array.

I put together a skeleton module which should be usable for any of the problems in this year’s Google CodeJam Programming Contest (as long as they don’t adopt a new format/pattern for the problems this year).

EDIT: Don’t use this package, but use instead Data.List.Split by Brent Yorgey.

I came up with what I think is an elegant use of monadic code, while working on a program to compute solutions to the Postage Stamp Problem.

This is my third post investigating compression techniques related to the DEFLATE algorithm: the first on run-length encoding, and the second on simple Huffman Coding.

This is the second of probably three posts (the first was on run-length encoding in Haskell) inspired by Thomas Guest’s interesting article on the Deflate algorithm.

Just a quick implementation of a RLE algorithm for lists in haskell.

I thought this was a good, simple example of how currying and partial application can be used in a very expressive way.

In my boredom, I implemented the toy sorting algorithm called Gnome Sort.

I’ve released my first package, up now on hackage (haddock docs should be generated soon).

UPDATE: I’ve just released this as my first package on hackage.

I’m working on a module called DirectoryTree, a simple tree structure mirroring the structure of a directory tree in the outside world, with functions to hopefully make it easy to do useful things (I’m not sure if something like this already exists).

This is to wrap up my previous post about Tries and my attempts at an implementation, and to summarize some of the things I think I learned about implementing a Trie structure in Haskell.

I have been interested in writing a Trie implementation to see how its performance compares to using Data.Map for storing dictionary-like data.

The Algorithm We can use Brent’s Algorithm to detect infinitely-repeating sequences in a list of values generated by some iterated function: that is, any list in which the next value in the sequence is generated from the previous value alone; if we find d…

GHC has an extension to the list comprehensions syntax that replicates the functionality of zipWith, by allowing you to have two generators running in parallel.

Update 1/1/2012: this blog no longer uses wordpress.

infixr 9 .: (.:) :: (b -> c) -> (a -> a1 -> b) -> a -> a1 -> c (.:) = (.)(.)(.)

A nice recursive algorithm for building a nearly-optimal binary search tree from an ordered list.: data Tree a = Node a (Tree a) (Tree a) | End The algorithm divides the input list into sublists of increasing length: 1,2,4,8… The first element

There are three identical functions in Data.Map for flattening a Map to a list of tuples in ascending order: assocs = toList = toAscList …but nothing to convert to a descending list.

This will be a blog about programming, mostly in the functional programming language Haskell.