dratewka has written 5 posts for dratewka

Loading log4j configuration from a file

Yesterday I needed to make log4j load its configuration from a specific file outside the classpath. Sounds simple enough and according to the docs all you need to do is setup an environment variable called log4j.configuration. The tricky part, which is easy to miss, is that the path needs to be given as a URI, … Continue reading

Analysing access logs using R

Recently I was analysing a bunch of access logs searching for some tricky to find bug and found out that R may be quite handy in such a situation. So let’s take a look at a quick analysis of access logs written in Common Log Format. Each line of an access log file looks like … Continue reading

AI overkill – Teaching a neural network to play Tic-Tac-Toe

In this post I would like to show you how AI can be used to teach a computer to play Tic-Tac-Toe… not the way it should be done 🙂 The game we’re dealing with is not very complicated to say the least and even if it was more challenging there are specialised methods just waiting … Continue reading

Generate Latex tables from R data frames

When writing reports using R + Latex environment it’s a good idea to directly generate the tables containing results of your calculations directly from R. This is rather a straightforward task when using commands like latex. One place when this gets a bit awkward is when you want to include some math in e.g. column … Continue reading

Latex symbols in R plots

Recently I’ve been making a lot of plots using R and I’ve reached the “I need some fancy math here” point. If you google around you’ll find the way to do this (for example or ) but I’ll post here a quick snippet anyway. One way of adding math symbols to your plots is using … Continue reading