Peter's Site - Geek stuff

Night time at the institute

nospam@example.com (Peter) — Wed, 28 Jan 2009 01:00:00 +0100

What could three PhD students do during night time when they are bored? Right, visit the local collection of formalin-conserved animals. I really think, one of the creatures moved while we didn't look at it..

Purple dragon is watching you procrastinate

nospam@example.com (Peter) — Wed, 01 Oct 2008 16:42:24 +0200

Today I built this tiny paper dragon which follows all my moves with great curiosity

Make your own!

Who (else) uses Twitter?

nospam@example.com (Peter) — Tue, 12 Aug 2008 18:20:46 +0200

After using Twitter for a some weeks now and finding it very entertaining, I wanted to investigate a little bit more in all the possible use cases and applications of this novel medium of communication.

First of all, the apparently huge constraint of limiting messages to 140 characters - which has nothing to do with SMS length - effectively turns out to be a great advantage. Authors are forced to write short and intelligible tweets, but in return, they can expect full attention by their readers - similar to news paper headlines.

My first contact with Twitter was during the landing of NASA's space probe Mars Phoenix on the Martian arctic surface. The Phoenix team had the great idea of using Twitter for writing updates during the landing - from the lander's point of view. Soon Phoenix' Twitter feed got more than 30k followers and it happily continues reporting on its experiments and discoveries. Now many people use Twitter to interact with the science team and ask all sort of questions about the mission and Mars, which Phoenix bravely answers. Probably surprised by the big interest in Phoenix' tweets, NASA set up many more Twitter accounts for other space crafts and experiments, probably hoping to achieve more public awareness and enthusiasm for NASA missions.
Public awareness is not only important for NASA - which continuously needs to justify its existence to American tax payers, but for basically every organization which depends on fund raising from the public. With Twitter's growing user base and thus many potential followers, I think we will see more and more organizations expanding to this new marketing channel, like the American Red Cross already does.
It's no surprise that Barrack Obama's campaign team makes heavy use of Twitter too and has most followers of all Twitter accounts - according to the ranking provided by Twitterholic .

Micro-blogging is also interesting for companies announcing new products or performing tech support - like Comcast is experimenting with. Users of open-source software can stay in contact with the developers and receive instant news about the software, e.g. Adium. Microformats.org is also twittering and keeps followers updated on the Microformats world. Fans of some fancy web companies can have a look behind the scenes of their dream employer.

Another big leap of innovation is Twitter's painless simple integration of SMS messages. Subscribers can choose if they want to receive SMS updates for each of the Twitter accounts they are following. Combined with several APIs and applications for publishing to Twitter, it becomes really simple to quickly send SMS messages to whatever intended audience.
This is particularly interesting for breaking news or for writing software agents. Since the availability of Twitter is pretty much unpredictable, it is certainly not suited for mission critical applications, i.e. you don't want to rely on receiving a Twitter SMS warning you of an imminent warp core breach. But there are many use cases for rather "informative" messages, like weather reports, earthquakes or even simple doorlocks.

So besides being an interesting tool for social connections, party announcements and Epeens, there are many uses out there for Twitter or micro-blogging in general and I am curious about that development in the near future.

The Bad News

Unfortunately, as of today Twitter discontinued sending SMS via their European number. They didn't manage to make reasonable contracts with the cell phone companies here and thus cannot afford sending SMS anymore. This is really disturbing, since one of Twitter's main features is lost, burying many use cases. Some users already lost all faith in Twitter. So we can only hope, this is only temporary and Twitter manages to get agreements with Europe's phone companies soon.

Blog und Twitter feeds kombinieren

nospam@example.com (Peter) — Tue, 29 Jul 2008 16:10:31 +0200

Eben hatte ich die tolle Idee, mal die Yahoo Pipes zu benutzen, um den RSS Feed jenes Blogs hier mit meinem Twitter RSS Feed zu einem einzigen Feed zu verbandeln. Prinzipiell könnten auch noch mehr Feeds einer Person (flickr, del.icio.us,..) eingefügt werden und man hätte quasi einen Feed pro Web 2.0 Entität (gibt's da schon nen ontologisch korrekten Ausdruck?).
Also habe ich fix eine neue Pipe angelegt, beide Feeds mit dem Union-Operator verbunden und zum Pipe Output geschickt (Pipe output RSS Feed). Das ist quasi der most basic Anwendungsfall für Pipes.. nur das es nicht funktioniert. Aus irgendeinem Grund antwortet Twitter auf den Request von Yahoo mit einem 406 HTTP Fehler. Naja, das wird sicherlich bald behoben werden, ich bin ja (hoffentlich) nicht der erste mit dem Problem.

Eigentlich wollte ich mit dem Post hier auch darüber hinwegtäuschen, dass meine letzte Blogaktivität schon etwas länger zurückliegt und ich atm mehr per Twitter schreibe und man das auch in seinem Feedreader lesen kann.

ZSH madness

nospam@example.com (Peter) — Thu, 20 Mar 2008 11:30:00 +0100

Ok, it's geek time now. If you don't know what a unix shell is, please scroll down, there are some non-geek blog posts with pictures and stuff.
After Sipprecht showed me his pimped ZSH prompt, my first thought was: "How ugly!", but a second look revealed some interesting features that prompted me to explore the Z shell a little bit further.

ZSH was introduced 1990 by Paul Falstad (OMG: what a geek, look at his geocaching.com stats!) as an enhancement of the bourne shell. It can be used interactively (i.e. you type commands) and as a scripting language. Besides being fully compatible with the bash shell, the Z shell has some original features and behaves much smarter in some situations. The most prominent changes that I encountered so far are:

The Prompt: It's possible to specify a left and a right prompt. The right prompt will disappear when typing long lines. Prompts are really a matter of taste, and these options make a customization of the prompt easier. My prompt now looks like this, with the working directory on the left and the time on the right. Note how zsh shows other user's homes with ~user instead of /path/to/the/user/dir.
Tab Completion: So that's the killer: If you deal with several files/dirs starting with the same characters and hit the Tab key, bash shows you a list of alternatives and you have to figure out by yourself the difference in the name and type an appropriate character to narrow the file list down. Very annoying. Especially when dealing with long similar file names, this behavior takes forever to find a single file. But zsh comes to the rescue: If you press Tab once, you see the list of alternatives and by hitting Tab again you can cycle through all the alternatives! With menu completion enabled, one can even navigate through the file list with the cursor keys and select the target.
Additionally zsh can expand substrings of file names. Say you have many P01XXXX.jpg files in your picture directory and want to pick P012344.jpg, then you could type 44 and press Tab and the shell will expand it to all files with 44 somewhere in their name.
Globbing a.k.a. Wildcard Expansion: Second killer: Everybody knows how to list a subset of all files in a directory by specifying a pattern, e.g. doing ls *.java to list all files ending with .java. If we wanted to list all java files, which reside in subdirectories, we need the help of find: find . -name "*.java". Not so in zsh which provides additional operators in file patterns. Here we use **/, and it will search all directories recursively: ls **/*.java.
Another huge advantage: After we type a pattern and hit Tab, if one or more files match the pattern, zsh replaces the pattern with a list of the matching filenames! Awesome. Now it's easy to see which files are affected by a pattern before executing a command, e.g. rm.