Posts tagged 'technical'

levien

Tips on designing, writing and debugging individual based simulations

This post was originally written in 2012, and was slightly updated in 2017.

When I first started writing stochastic, individual-based computer simulations in 2005, I thought it would be a pretty straightforward job. Although I'm technically a biologist, I already had quite some (self-taught) experience in C-programming and knew about …

levien

On Filesystems

This article was originally written in 2011, and was slightly updated in 2014.

Filesystem types and (lack of) compatibility

Despite the fact that we're no longer living in the 1980s, filesystem-compatibility between operating systems seems to remain an issue in computer-land. The filesystem basically defines the way in which files …

levien

Video Processing and Encoding

For a couple of years there have been a number of great open-source programs around for encoding video, both in Windows and (Ubuntu) Linux. Some of them provide a nice graphical user interface, but the best ones are still commandline tools, such as ffmpeg and MEncoder. They are extremely flexible …

levien

Tweaking Ubuntu for the Lenovo Flexpad

I don't like to get new equipment if I have old equipment that still works fine. My Asus A2500S laptop is now more than 10 years old, and although it has received a few small repairs and a memory upgrade over the years, it still works fine. Its Pentium 4 …

levien

Replacing the volume knob on a Kenwood amplifier

For some reason, repairing broken equipment is one of these tasks that I tend to put off for months, if not years, because it feels like it's going to be a lot of hassle.

About a year ago the volume knob broke off my Kenwood KRF-V5090D audio video surround receiver …

levien

Assorted Ubuntu Problems (and how to solve them)

This article was written in 2010 and was slightly updated in 2013 and 2017.

I've been running Ubuntu as my main operating system since around 2004, and I must say I love it. However, every OS has its problems, and Ubuntu is no exception. Here's a few I ran into …

levien

Adventures in online lectures

A few weeks ago I started teaching a mathematics-course for first-year biology students, as part of a larger three-month Systems Biology course at the University of Utrecht. A couple of years ago the university started to record a number of its lectures, which were then made available online for students …

levien

LaTeX formulas in ODF and Word documents

UPDATE (2012-10-01)
OOoLatex is no longer being updated by Geoffroy Piroux. Roland Baudin has created an up-to-date fork for LibreOffice called TexMaths. To install that on a recent version of Ubuntu, first get the required packages:

sudo add-apt-repository ppa:martin-gieseking/ppa
sudo apt-get update
sudo apt-get install texlive dvipng dvisvgm …
levien

Fixing video drivers in Linux

One of the drawbacks of a monolithic kernel is that you're often stuck with outdated drivers that don't work for your hardware. Even if a fix is available upstream, there's no easy way to update just a single driver. Luckily, LinuxTV now at least offers a script to automatically recompile …

levien

PDF Tips & Tricks

Repairing a damaged PDF-file

Ghostscript can "repair" some damaged or buggy PDF-files, by regenerating them. Try something like:

ps2pdf damaged.pdf fixed.pdf

Believe it or not but ps2pdf will happily accept PDF as input, and from it create a new PDF... You can use all the usual Ghostscript options …