O(n) Delta Compression With a Suffix Array

The difference between two sequences A and B can be compactly stored using COPY/INSERT operations. The greedy algorithm for finding these operations relies on an efficient way of finding the longest matching part of A of any given position in B. This article describes how to use a suffix array to find the optimal sequence of operations in time proportional to the length of the input sequences. As a preprocessing step, we find and store the longest match in A for every position in B in two passes over the suffix array.

How wide should you make your web page?

Based on 22500 unique IP addresses over the past week.

What does your phone number spell?

Here, I explain a technique for figuring out which words are in which phone numbers. Full C source code is included.

See sound without drugs

I have created an application that just turns on the microphone and continually plots the FFT magnitude of what it records. It allows control over the window size and sampling rate.

Fun with Colour Difference

Are you looking for a nifty way to choose colours that stand out? Are you the type of person who is not satisfied until you have mathematically proven that your choice is optimal?

Simulating freehand drawing with Cairo

Tool for Creating UML Sequence Diagrams

If you have to draw something called "UML Sequence Diagrams" for work or school, you already know that it can take hours to get a diagram to look right. Here's a web site that will save you some time.

An instant rhyming dictionary for any web site

Sometimes your API has to be simple enough for non-technical people to use it. Find out how to include a rhyming dictionary on your web page just by copying and pasting.

Pitching to VCs #2 (comic)

Fast and Easy Levenshtein distance using a Trie

If you have a web site with a search function, you will rapidly realize that most mortals are terrible typists. Many searches contain mispelled words, and users will expect these searches to magically work. This magic is often done using levenshtein distance. In this article, I'll compare two ways of finding the closest matching word in a large dictionary. I'll describe how I use it on rhymebrain.com