Intrepid Blog

Dutch student protest

Bas Westerbaan — Sun, 31 Jan 2010 13:08:35 +0000

This week, various student organisations protest against major cuts in the funding of education and research.

A reader of dutch, can visit their site.

Unique followers on Twitter

Bas Westerbaan — Wed, 16 Dec 2009 18:27:12 +0000

As pointed out by Jorg Kennis, Twitter’s new lists feature make it hard to determine the amount of unique followers. I’ve written a simple script, using a slightly modified TweePy, to determine the amount of unique followers.

Example usage:

bas@w-nz ~/twitter-unique-followers $ python twitter-unique-followers.py JorgK -ubwesterb Password: rate_limit_status: remaining_hits: 112 Jorg Kennis followed directly by 182 in lists RPtje/vriendenbekenden subscribed to by 0 JorgK/TechNL subscribed to by 0 sentfanwyaerda/nijmegen1 subscribed to by 9 JorgK/Friends subscribed to by 0 sjorsjes/Community subscribed to by 0 robinspeijer/iPhone subscribed to by 1 nielsschooneman/iPhone subscribed to by 0 JeanPaulH/iPhoneclub subscribed to by 5 number of unique followers: 198

You can download it here. I could write a simple webpage with the same functionality, if anyone would mind.

Normul

Bas Westerbaan — Sun, 01 Nov 2009 11:18:03 +0000

Normul normalizes URLs. It expands shortened URLs:

>>> from normul import normul >>> normul('http://bit.ly/1I4VQ') {'type': 'other', 'normalized': 'http://www.shinguz.ch/MySQL/mysql_mv.html', 'original': 'http://bit.ly/1I4VQ'}

And shows useful links for hosted-images:

>>> normul('http://yfrog.com/6c5krj') {'image': {'full': 'http://img228.imageshack.us/img228/1079/5kr.jpg', 'thumbnail': 'http://img228.imageshack.us/img228/1079/5kr.th.jpg'}, 'type': 'image', 'original': 'http://yfrog.com/6c5krj', 'normalized': 'http://yfrog.com/6c5krj'}

You can find the simple but convenient sourcecode here.

Cantor never bores (1)

Bas Westerbaan — Sat, 24 Oct 2009 20:11:23 +0000

Given a set of countable sets , such that is totally ordered by inclusion, videlicet for every either or . Intuitively, for at every step in this chain one element at least must be added, one expects the set to be countable as well.

Suppose is countable. Then the union, is a countable union of countable sets, hence countable. (Suppose is an enumeration of and enumerations of the elements of the chain. Then enumerates .)

Thus is an upper bound of . In the poset of countable subsets of some set , of which is a subset, every non-empty chain has an upper bound. Hence, using Zorn’s lemma there is a maximal element, say .

Suppose is uncountable, then there exists a . is most definitely also countable and which contradicts ’s maximality. We are forced to conclude that there exists an uncountable chain of countable sets.

Cantor’s set theory keeps surprising.

Update: an example of such a chain is the set of the countable ordinals.

Another update: a “more concrete” example are the downsets in without the empty set and itself. These downsets correspond to real numbers, see Dedekind Cuts.

Bond against Loanwords

Bas Westerbaan — Wed, 09 Sep 2009 23:37:14 +0000

Although I don’t bear any animosity against most dutch loanwords (except those Anglo-Saxon), the dictionary of the dutch Bond tegen Leenwoorden is a true joy to read.

21

Bas Westerbaan — Mon, 31 Aug 2009 10:18:48 +0000

Since yesterday I, for the first time, enjoy the anything-but-special age of 21 years.

Windows 7 Sins

Bas Westerbaan — Thu, 27 Aug 2009 13:06:16 +0000

Windows 7 Sins. I strongly agree with points 1, 3, 4, 5 and 6. The arguments for points 2 and 7 are a bit weak, but I do agree with the conclusions.

For the non US audience, it would have been nice to note that if Microsoft (or the US) would recall all foreign licenses for Windows, our entire government is crippled.

Twitter and Facebook

Bas Westerbaan — Thu, 06 Aug 2009 23:46:19 +0000

were both victim of a DDoS today. Silently, I always hoped that a really long-lasting one will convince them to put effort in a distributed scheme.

Maybe I should be waiting for another Wave.

PijsMarietje

Bas Westerbaan — Wed, 01 Jul 2009 15:58:44 +0000

At the faculty for sciences there are canteens for students. In each of these, there’s sound equipment connected to linux boxes. On each of those linux boxes, we run a music-request-server called Marietje. I just finished writing a front-end in Javascript. It wasn’t a pain. As instead, the use of jQuery was a bliss.

The frontend for one of those boxes and the source code (see the ajax folder).

Damned DOM (1)

Bas Westerbaan — Mon, 22 Jun 2009 14:34:51 +0000

When I wanted to react to any changes to a input textbox immediately, my first instrinct was to use onChange. onChange, however, is called when the input loses focus. onKeyPress then? Isn’t called on backspaces. onKeyDown, maybe? It does get called, but the effect of the keystroke isn’t yet applied, for the return value determines whether it that is done in the first place. (Same story for onKeyPress by the way.) onKeyUp does work a bit, except if someone is holding down a single key, for a while.

The solution: hook onKeyUp and use setTimeout with a timeout of 0. Yugh. I hate DOM.

Big Fat Disclaimer: I actually tested this only on one browser.