Problem The primes 3, 7, 109, and 673, are quite remarkable. By taking any two primes and concatenating them in any order the result will always be prime. For example, taking 7 and 109, both 7109 and 1097 are prime. The sum of these four primes, 792, represents the lowest sum for a set of [...]

Besides having one of the coolest names around, Random Forest is an interesting machine learning algorithm, for a few reasons. It is applicable to a large range of classification problems, isn’t prone to over-fitting, can produce good quality metrics as a side-effect of the training process itself, and is very suitable for parallelization. For all these reasons, I thought it would be interesting to try it out in F#. The current implementation I will be discussing below works, but isn’t production ready (y[...]

We recently found out about an interesting, undocumented behaviour of Amazon’s Elastic Load Balancing (ELB) service – that health check pings are performed by each and every instance running your ELB service at every health check interval. Intro to ELB But first, let me fill in some background information for readers who are not familiar [...]

Close your eyes and imagine your program as a function that takes a set of inputs and produces a set of outputs. I know this may seem overly simple, but a set of actions in a GUI can be thought of as a set of inputs, and a set of resulting side effects to a [...]

I just completed the Coursera Machine Learning class this week, and enjoyed the experience very much. Let’s get the obvious out of the way: getting a high-quality class, for free, wherever you are, at your own pace, is pretty amazing, and I can put up with a sometimes flaky video player for that. Every quarter in college, I would agonize over what limited number of classes I should take, thinking that I might not be able to take that class ever again once I graduated, and Coursera is awesome for that – now[...]