I am a big fan of the old Japanese board game Go. Some time ago I wanted to get my own Go game, consisting of a Go board (goban) and black and white stones. Unfortunately, I found out that wooden Go boards are quite expensive, by far exceeding the price range I was willing to pay. Actually, gobans are quite a simple piece of equipment. It is nothing more than a (wooden) board with a grid of 19 x 19 lines on it, why should I pay over 100 euro for it? So I decided to build my own and just buy the stones, which are cheap to come by.
I’ve received my rPi a while ago, but never wound up doing much with it. Recently I have received another screen which is a little older, but still features a DVI input. Since developers can’t have enough screen space and my laptop has only one VGA output, I decided to use the raspberry pi as my ethernet-to-DVI adapter.
This how-to is composed of two parts, first I explain how to get synergy up and running, and then how to set up your VNC to help the illusion that everything is happening on the same computer.
As mentioned in an earlier post, I’m currently writing a music streaming server in python. As I wanted to go with the newest thing available, I wrote it in python 3. Unfortunately the application server we rely on, cherrypy, is only packaged for python 2 in most distributions! Even worse, even if the packages were installed for python 3, it would not run, since I relied on python 3.3 features.
Since this keeps my program from being used in the world, I decided to backport it to python 2. For me it was very important, that the code would not get any uglier by doing so, so I started writing a replacement module.
Here’s a collection of useful code snippets to help you making your software python 2 / 3 compatible.
I finally got myself a Raspberry Pi and it obviously needs a case. (By the way, it runs the ARM version of Arch Linux, naturally.) Of course I wanted to build one myslef, rather than buying one of those boring cases that almost cost more than the device itself. I already had a vague idea about the concept but nothing solid yet. The concept had to be simple (but solid), because besides a Dremel and an electric drill I only had standard tools at hand. (You do not even need a Dremel if you have a small saw instead.)
I recently wrote a Music Streaming Server in python, that allows you to listen to your music inside a browser, no matter where you are. It is called CherryMusic and features a standalone webserver based on cherryPy as well as JPlayer, a HTML5/Flash music player. It indexes your data for fast search using a sqlite database, so there is nothing to setup for you, just download the sources and off it goes!
In my tests it works perfectly with many thousand indexed files: searches are returned immediately, even on my little home server.
After the break you can find some screenshots of it in action.
I recently saw a video of an implementation of Conway’s game of life written in APL which was done in just one line. And because I couldn’t sleep last night, I implemented it in python as short as I possibly could.
So here it is:
for j,i,nb in map(lambda j:(j,j+s+1,bin(life&((7|5<<s|7<<s*2)<<j))[2:].count('1')),map(lambda x:x+int(x/(s-2))*2,range(0,(1<<s-2)+1))):
next = next|(1<<i)^(1^(((('23'.count(str(nb))<<1)+'3'.count(str(nb)))>>((life>>i)&1))&1))<<i
There’s a little write-up and the source after the break.
I recently needed to get some data out of a large tar file, about 5gb in size, that I didn’t want to extract, as it contained many thousands of small files. Unfortunately the tar format was not designed to be indexed, since it was meant for backups on magnetic tapes (tar stands for tape archive). The gnu tar has a command for retrieving single files, but it needs to go through the whole tar each time, which was just not doable.
So I decided to write a little tool, that would index the files and write that index to another file. Now I can access each file within the tar in just a second, instead of 15 minutes. Introducing the tarindexer!
This post describes a dirty (but effective) workaround to individually disable data synchronization of the installed Google apps, while keeping others (e.g. Android Market) intact.