Lately I've been spending some time thinking about URL shorteners. The interest arose over a recent weekend as I sent someone shortened URLs to a couple of sites, that I had bookmarked a few years ago. I'd inadvertently bookmarked the shortend links rather than the long URLs, and my reciepient complained that they couldn't read the content I'd sent them. Some investigation later, I realized that their mail system may have been blocking the URL. In addtion, one of my other shortened links had 'expired'. The short URL no longer worked. That sparked off a series of technical explorations that are now the subject of these blog posts. (Full article)
Thoughts on technology, computer science, mathematics, and programming. And not necessarily in that order!
Sampling from a Bivariate Normal Distribution
Most math libraries have a random number generator that generates samples from a normal distribution. Many libraries, like Apache Commons Math have random number generators that generate normally distributed scalar variables (i.e. samples from univariate normal distribution.) The task of generating random samples from a bivariate normal distribution, given a univariate normal random number generator is a little more complex. This is the subject of this post. (Full article)
Series: Using Java applets and applications portably
Java applets on web pages create some problems, the biggest of which is that the default way of launching them is unfriendly to users. Furthermore, the default launch techniques are not very browser friendly. Finally, there are annoying differences between UI initialization code for applets and applications. This article is the first in a three part series that describes solutions to these problems. (Full article)
if control construct is a special form in Scheme.
This note examines why this is the case.(Full article)
A short note on how Scheme differs from C when it comes to recursive tail calls. Inspired by a problem set in the book The Structure and Interpretation of Computer Programs. (Full article)