Open-Source

This is the “shortcut” sequence of keys in order to get the list of changes in a text document in OpenOffice.org. It works very nicely with MS-Word documents, a useful feature when you are obliged to exchange work with colleagues, mentors, etc. who only use the proprietary word processor. IMHO, the only problem is the way the list of changes is shown to the end-user in OpenOffice.org: as in other word processor software, changes are underlined in a different color for each contributor and a small hint tells you what happened to the hovered block of text, who did it and when; unlike other word processors, you can’t accept/refuse any change by right-clicking on it (you have to do it from the separate window). I do not find this intuitive and, sometimes, annoying … ...

When you are used to work on a computer with GNU/Linux and are obliged to process your files on a MS-Windows system for some time, the GnuWin32 project can come in handy. They provide a lot of command-line tools from the GNU collection (sed, iconv, tar, bzip2, … see the whole list of packages they provide). This evening, I needed to convert a lot of files from UTF-8 to iso-8859-1 (because it seems no decent Windows text editor can correctly translate text between these two encodings). Apparently, the GnuWin32 project removed the recode tool. But it can be easily replaced by iconv. With iconv, it’s done with: ...

I don’t know how I stumble upon this report of a conference ( English translation) from Avi Alkalay but I liked 2 schemes he showed. In this first scheme (left), I like the way it reminds you that “Open” is not only about software, source code. But now that more and more people are aware of the benefits of Open Source software, it’s interesting to also stress the other sides of openness: open standards (like OpenDocument), open hardware, open architecture. In the second scheme (below) is about the trend from private control / closed access to public control / open access (apparently from Rebecca Henderson; it could be interesting to find this whole presentation from 2004). ...

After the promotion of Open Access (see Bernard Rentier’s blog) and a history of publications in Open Access journals (see this last article from the Cyclotron Research Center in PLoS), the University of Liege is slowly slowly publishing Open Source software too. The last free software published is exams, an assessment management system (for on-line exams, …). They chose the GNU GPL 2, apparently without the possibility to upgrade to version 3 (I don’t know if it’s deliberate or not). And you can download the source code here. ...

I was writing the next version of my badge counting the number of days without Belgian government when Laurent added his comment requesting for a vertical version. You can see it on the right. Since the original release, I also added translation of the sentence in Dutch and German (after all, Belgians are speaking 3 official languages). And I approximately centered the text on the vertical version (I personally prefer the text on the right for the horizontal version but you can easily modify this by yourself). ...

Now it’s not a secret anymore: more than 148 days passed since we, Belgians, went to vote (it was on the 10th of June 2007) and we still don’t have any government! If you want to count the numbers of days without Belgian government, it’s easy: just have a look at Belgian newspapers. Or … have a look at the counter below (in French, Vlaams or German) ;-) ...

Following a comment from Alexandre on a previous post, I went a little bit further with my performance test of database engines running under Java. This evening, I tested a profiling tool and a variable number of insertions/retrievals (I didn’t tested transaction). Taking the code from the previous time, I simply changed the number of elements to be inserted/retrieved. As expected, the durations of object initialization (except for 2 points for Derby and H2) and database creation did not change with the number of elements to be inserted, Derby being still the slowest engine to create a simple database (1 table only). The durations of the insertion step increased slowly with all the database engine, except for SQLite+JDBC: you can see a much steeper initial angle in the increase of the duration in the graph below (be careful: x-axis shows logarithmic values). ...

Following a comment from Alexandre on a previous post, I included SQLite in my performance test of database engines running under Java. What prevented me from using SQLite in the previous test is that it’s not a pure Java database and one have to use third-party JDBC driver and implementation classes in order to manage this database engine. IMHO, I also dislike another fact: SQLite does not enforce data type constraints ( and it’s a feature, not a bug) so everything is stored as ASCII string, even if you have very few other “artificial” data types. ...

I’m wondering why Sun chose Derby for its JavaDB … I used JavaDB on a project and my main reason was that it’s embedded in the last Java Runtime Engine (JRE). But I saw a clear degradation of performances (my main criteria is speed) when I had to access the embedded database. And it became worst when I ran my project from a CD-ROM (because it has to be distributed). So I decided to run a small, rough test and compare JavaDB with two other free Java database engines: H2 and HSQLDB. And the results are astonishing: JavaDB seems to be the slowest, hence the worst choice (except for the license). Here are the results (click to show the normal size graphs): ...

Someone hoped my laptop doesn’t make too much noise after I posted a photo of the Tecra logo on Flickr. The short answer is no, it doesn’t make too much noise. At 10cm from the fan output, I can measure 42 dB when the fan is off and 52dB when it’s on. Beside the fact that I don’t hear that noise when I have my headphones, it was not sufficient for me. I wrote small python and gnuplot scripts to collect and display temperature, fan status and load ( .tar.gz file, 1.3ko). During those 2 hours, I checked my e-mails, read news on the web and wrote the OPML output in catrss (that’s why load averages increase at the end, when I’m debugging the software). Here are the results (click on an image to see a larger version): ...