Stefan Seemayer - Semicolon Software

Python Decorators, Explained

Decorators in Python are a very powerful albeit mind-bending and under-documented tool. They are useful for many things, including changing how a function is executed (e.g. for denoting that an API endpoint requires authentication) or to register a function as a handler (e.g. to register different parser functions

programming

D/Tox - Will it cure you or kill you?

For this year's christmas project, I have worked on a little game idea — introducing D/Tox, a game that lets you figure out if you can tell if a molecule is good or bad for you. D/Tox main game screenThe game will randomly select 10 out of a set

rust

Marching Squares in Rust+WebAssembly

After previous forays into creating fancy backgrounds using JavaScript, I've been playing with an implementation of one of my favourite computer graphics algorithms in Rust. It seems that my second, more efficient implementation is a lot faster than the old JavaScript code (I didn't benchmark them side-by-side but it is

rust

Cross-compiling Rust Code using GitLab CI

I've been excited to learn the Rust language for two years now since it compiles the performance properties of statically-compiled languages with modern language ergonomics (and allows you to parallelize things you normally wouldn't dare to thanks to its safety model). Another nice, less highlighted aspect of Rust is that

programming

A bot that learns how you play rock-paper-scissors

As a small project, I wrote a bot for learning player patterns when playing rock-paper-scissors using a first-order Markov chain. This is definitely not the first time someone has had this idea, but I still thought I would give it a go. My implementation simply models a combination of computer

webdev

Well-brewed tea made easy, thanks to technology!

I enjoy Japanese and Chinese loose-leaf tea. A lot. To get the most out of the tea experience, there are many things to take into account. In fact, to have a perfectly brewed tea it should have the following aspects taken care of: water temperature, water quantity water hardness, tea

Building Minimal Docker Containers for Rust Applications

Inspired by Nick Gauthier's work on building minimal Go containers and Erik Kidd's work on simple compilation of Rust binaries with no dependencies, I was curious to see how small a comparative Rust container serving HTTP via the Iron framework could be. In this article, I will be combining an

javascript

Programming R like it's JavaScript / Python

R is the king of statistics languages for a good reason: There are hundreds of packages on CRAN for all sorts of analyses and the language is fluent for processing data in a variety of ways, especially when taking advantage of the hadleyverse packages. In my opinion, dplyr is the

javascript

Generative Art for Website Backgrounds

Since my personal website Semicolon Software doesn't need to contain much more than a few links into different places on the web, I wanted to make it more interesting by doing some JavaScript experimentation. The result of this is a beautiful piece of randomly generated background art every time that

python

Compiling Python, NumPy and SciPy with Intel Compilers and Intel MKL

Compute clusters are shared machines so they often contain very outdated versions of software in the name of backward compatibility. While the environment modules project goes a long way of alleviating this problem, I often encounter problems with the Python installation on clusters that I'm working on. In such a

webdev

Blissful Personal Project Deployment: Dokku + Let's Encrypt = 😁

Update: I no longer use Dokku and the Let's Encrypt plugin is no longer maintained or working. Please look for a new solution! If you are like me, you have a ton of personal programming projects lying around from weekend experiments sparked by your latest idea. At the end of

security

Running dokku-letsencrypt auto-renewal as a Cronjob

With the new letsencrypt:auto-renew command added to my dokku-letsencrypt plugin, it is now super-easy to set up automatic certificate renewal on your host! Here's a guide on how to configure cron to perform a daily check and auto-renewal for your Let's Encrypt certificates. Note: I'm using the dokku-recommended Ubuntu

webdev

Securing Dokku with Let's Encrypt TLS Certificates

TL;DR: My letsencrypt plugin for dokku makes securing dokku webservers with HTTPS a breeze. Update 2016-01-12: In the meanwhile, my plugin has become the official letsencrypt plugin for dokku. Additionally, some usage and implementation details have changed so I've updated the post to reflect the new status. Update 2016-03-08:

python

Inspecting multidimensional C/C++ matrices by putting NumPy into GDB

Developing numerical programs in C, C++ or Fortran or even just fast C extensions like in my previous post, the chance of introducing a bug increases as complexity increases. One of my favorite types of bugs are caused when working with multi-dimensional arrays. While multi-dimensional arrays are relatively painless in

analyses

The most popular random seeds

When developing programs that rely on some sort of randomness, it is often a good idea to make the random number generator behave more deterministically. For example, you could have a procedurally generated game generate its content based on a random seed that could be exchanged by players to play

hpc

Fast Interstellar Travel with NumPy and C

I absolutely love Python (and NumPy!) for the flexibility it gives me in quickly building up complex data structures and programs to arrive at interesting solutions. Still, sometimes handling larger amounts of data is too slow even after profiling my code and subsequent performance tuning. In those cases, going more