Computers on Jean-Etienne's blog

Start with a PyPortal in 2021

Sun, 04 Apr 2021 17:53:57 +0000

The Adafruit PyPortal is a great device, with a few bells an whistles already integrated in order to start small electronic projects (but expensive, ok ;-)). As usual, Adafruit wrote a nice introductory guide. But some parts are outdated. Therefore, here are a few steps to get you started with CircuitPython on a PyPortal in 2021 …

Programming Merit Badge presentation (2020)

Sun, 02 Feb 2020 04:29:08 +0000

This year, my elder son graduated from Cub Scouts to Scouts (time flies very fast!) and I signed up to be a counselor for Programming (and Public Health) in his troop.

Today, February 1st, 2020, was Merit Badge Day and I taught 6 scouts what is programming and the basics of programming in Python (and Scratch - but they all knew that already) (and nobody chose Public Health …).

I am now sharing my presentation and a few tips and tricks. Feel free to re-use, improve and give me any feedback to make it better.

Digitize you charts with Engauge Digitizer

Fri, 04 Aug 2017 16:31:39 +0000

A few words of appreciation for an open source software that can help you a lot in your work, Engauge Digitizer (ED) from Mark Mitchell. ED is a simple, straightforward curve digitizer: it takes images with graphs like the one below and transform them (with a little help) in data you can use later on.

How to redesign a numeric keypad?

Mon, 11 Jan 2016 22:09:10 +0000

In an interesting blog post on Smashing Magazine, C.Y. Gopinath explained the design choices he made to build a new calculator for smartphones (iPhones more specifically). He started with an interesting summary of the reasons and origins of the numerical keypads of phones and calculators (keyboards, ATM, etc.). This is what drove me to read his post. Indeed I posted a photo on Flickr that showed the difference, a few years ago.

Fedora 23 on a Dell XPS13 (part 1)

Thu, 17 Dec 2015 21:05:40 +0000

Taking advantage of a trip to Canada and a very favourable CAN$:€ exchange rate, I bought a Dell XPS13 (9350 or “late 2015”), following excellent reviews from around the web. Dell sold a ’ developer edition’ of this laptop (shipping with Ubuntu Linux) but unfortunately it was out of stock on Dell US and I couldn’t find the item on the Dell Canada website. So I bought the Windows version with a touchscreen (it was Black Friday :-)).

Here is how to install Fedora 23 on it (and probably most other Linux distribution) … I will focus on three aspects (in brief: everything works out of the box, except the wireless card that needed some additional action):

How to boot and install Fedora Workstation
What works and what doesn’t work out of the box
Some things to do after installation (additional software)

Import PDFs and related metadata in Zotero

Thu, 03 Dec 2015 19:14:38 +0000

I discover new things everyday …

I wrote earlier that I really liked Zotero, a reference management software. However, there is one thing that was missing, imho: the capability to import PDFs (individually or in bulk) and correctly fill in the various fields of the reference.

But in fact, this already exists in Zotero! Just drag a PDF in the middle section (the reference list) then right-click on it and choose “Retrieve Metadata from PDF” (*). Retrieval of the title, the authors, the journal, etc. everything goes very fast and they are stored as a normal reference, now on the right.

Jadoo and static website generators

Wed, 18 Nov 2015 19:03:10 +0000

Coming back from holidays, I fired my RSS reader and, among many interesting posts, I found this one from Smashing Magazine about static website generators being the Next Big Thing on the web (and a follow-up deep-diving into four of them).

The first paper describes how the web started as something static, became all dynamic and is progressively coming back to something more static, at least for some specific tasks. The interesting thing is that the author also describes pros and cons of each stage and why the web jumped to the next level.

Happy to use Zotero since a few weeks

Fri, 26 Jun 2015 19:33:24 +0000

For my work I need to reference a lot of statements, mainly with papers and books in the biological / medical literature. Usually “professionals” use two proprietary software, Reference Manager or EndNote (both owned by Thomson Reuters). But there are a few very interesting free alternatives (see this comparison of reference management software).

I switched from Mendeley to Zotero a few weeks ago and I’m very happy. Here is why …

Creating presentations with non-WYSIWYG tools

Sun, 24 Nov 2013 00:44:32 +0000

I work in a company that shifted from being R&D-driven to being project-driven. It is official since this 2013 but we saw it coming: the main pieces of memory are Powerpoint slides since a few years.

Everything is in Powerpoint, from agendas, discussions, presentations to minutes. Even when modelers want to show some results, they put them on a slide deck first …

For presentations I used to use Beamer but installing the LaTeX toolchain on a restricted, company-owned Windows laptop was a long and cumbersome process. I made a first presentation in Reveal.js this week. And I love it!

Privacy -vs- information conservation time

Mon, 28 Oct 2013 11:27:42 +0000

In my opinion privacy issues are a by-product of information conservation times reaching infinite.

For centuries and more humans were used to their own type of memory. When information reaches the brain, it is stored in short-term memory. When relevant and/or repeated, it is gradually consolidated into long-term memory (this is roughly the process).

The invention of oral transmission of knowledge, written transmission (incl. Gutenberg) and, to a certain extend, internet, all these successively increased the duration of retention of information shared with others. The switch from oral to written transmission of knowledge also sped up the dissemination of information as well as its fixed, un-(or less-) interpreted nature.

Is it so difficult to maintain a free RSS reader?

Mon, 05 Aug 2013 12:04:10 +0000

A few months ago Google decided to retire its Google Reader (it stopped working on July 1st, 2013). As it was simple, effective and good-looking, a lot of people complained about this demise. A few days ago The Old Reader, one of the most successful replacement for Google Reader, also announced it will close its gates, only to keep early registered users. And today Feedly, another successful alternative, announced it is introducing a pro version at 5.00 USD per month.

How to write data from R to Excel (even if you don’t have Excel)

Tue, 21 May 2013 20:42:15 +0000

Following my previous posts on how to read/write Excel files from Matlab here is the way I use to read/write Excel files from R. Again it seems the Apache POI java library made developers’life easy. I use here the simple-yet-powerful xlsx package ( documentation here in PDF; project website).

Here you don’t need to install any additional files, installing the xlsx package from R does all the dirty work that for you. Then, reading an Excel file is very easy:

Any free solution for the demise of Google Reader?

Mon, 25 Mar 2013 10:56:09 +0000

Last week Google announced it will shut down its Reader service. It is a web-based RSS reader. It therefore allows to be kept updated of news from around the net in a central location. I liked the service for 3 reasons (on top of the fact it’s free, 0$, to use):

It’s web-based, accessible from anywhere/everywhere with a simple browser;
It’s text-based, you can quickly scan headlines and use the powerful search function from Google;
It’s backed by an API so you can use it via different apps on different platforms and they all stay synchronised (the web/mobile version of Reader is not as efficient as the web/desktop version; hence the proliferation of apps using Reader as a backbone).

Of course it frustrated a lot of people, from scientists to consultants … to name a few only. People are looking for alternative ( you can do a search on Google while the Search service is still working). Feedly is cited very often as the next best alternative. However its nice, graphical interface conflicts with my second reason to like Google Reader: it’s text-based. The Old Reader looks also interesting, it is text-based but no apps on different platforms yet. But both are also proprietary and can be turned off (or changed to a pay-for-use model) at any moment :-(

Map of GAVI eligible countries in R

Sun, 10 Feb 2013 22:48:45 +0000

I was trying to reproduce the map of the GAVI Alliance eligible countries (btw I was surprised India is eligible - but that’s the beauty of relying on numbers only and not assumptions) in R. This is the original map (there are 57 countries eligible):

I started to use the R package rworldmap because it seemed the most appropriate for this task. Everything went fine. Most of the time was spent converting the list of countries from plain English to plain “ISO3” code as required (ISO3 is in fact ISO 3166-1 alpha-3). I took my source from Wikipedia.

Android is catching up iOS

Fri, 21 Dec 2012 11:08:52 +0000

Well, there is nothing new in this statement. The smartphone OS Android is catching up and even overtaking its rival iOS in many domains:

more activated products per day and per year in 2011,
more Samsung Galaxy S3 (running Android) sold in Q3 2012 than iPhone4 and 5S (running iOS),
more devices worldwide,
catching up Apple’s market share in tablets,
…

All this is summarised in an infographics MBA Online designed (the original address is here: http://www.mbaonline.com/android/ - click at your own risk). It is sweet and colorful, with lots of numbers and some references in the end. Unfortunately these references are embedded in the image so you cannot click on them if you ever want to read more info.

How to write data from Matlab to Excel (especially when you don't have Excel)

Tue, 11 Dec 2012 13:09:50 +0000

If you are using Matlab on a MS-Windows PC with MS-Excel installed, there is no problem reading and writing data to Excel (in case your users/customers only understand this software but you still want to do the computations in Matlab). Here is the code to read (1st line) and write (2nd line):

[sourcecode language=“matlab”] inputs = xlsread(‘inputfile.xls’, ‘inData’, ‘A1:B3’); [writeStatus, writeMsg] = xlswrite(‘outputfile.xls’, myMatrix, ‘outData’, ‘A1’); [/sourcecode]

Now, there are several reasons why you may not be able to read and write directly to an Excel file: you have Matlab but

Android-based smartphones market share in Asia

Fri, 23 Nov 2012 23:01:57 +0000

31%

Tonight I was wondering what was Android market share in Asia. It is 31% according to a recent study from Ericsson’s ConsumerLab group ( reported by TechRepublic). Although dominant through most studied countries, Android is not dominant in Singapore (iOS has 46%), in Indonesia (RIM has 29%) nor in Vietnam (Symbian has 26%).

Last year ABI Research released a study where they showed that Android-based smartphones market share grew from 16% in 2010 to 52% in 2011 (but this included tablets and did not cover exactly the same countries as the Ericsson study). Voila :-)

Idea shared #2 - the feedback toothbrush

Mon, 22 Oct 2012 21:26:28 +0000

After the T-shirt that measures your sleep better than an app, here is idea #2: the toothbrush that provides some feedback.

The idea is simple - so simple it was already applied elsewhere. The idea is to provide feedback about the quality of the way people brush their teeth. The Brushduino focuses on entertaining kids to keep them brushing at the right place for the right amount of time. Other projects (with many variants) focus specifically on time spent brushing.

Idea shared #1 - measure your sleep

Sat, 22 Sep 2012 21:48:32 +0000

I don’t consider having more or better ideas than others. But I gradually realized I have less and less time for some activities like programming, electronics etc. Maybe that’s how we realize we are getting older now adults. So I decided to share these ideas rather than fueling the illusory idea that I will implement them one day.

So idea 1 is about measuring sleep. I recorded animals’sleep during my Ph.D. - but it was thanks to an EEG device. I think that if you want to understand or improve something you have to first measure it in a way or another. So I started to try to measure my own sleep with an app ( Sleep Cycle). But despite its good reviews it doesn’t work, at least for me.

The 6 Android apps I really appreciate(d)

Thu, 26 Jan 2012 21:51:20 +0000

For some reasons, I had to choose between a new, simple Nokia phone (but fortunately not a Windows one!) and my 1-year-old Android phone. Before I leave this Android phone, here are the few 6 Android apps that I really appreciated and used daily.

FBReader is a very nice e-book reader for Android. It supports a lot of e-book formats like epub, fb2, (partially) mobipocket, html, RTF and plain text. It works very well with Calibre (a free software e-book reader / manager / converter) - or is it the opposite? I also really like the fact FBReader can browse and download some free e-books directly from the internet. Of course, reading an e-book on a small 3.2 inch screen isn’t the perfect user experience. However, the night mode (white text on black background) is very handy to read something when it’s late and you don’t want the harsh white background. You can find FBReader on the Android Market for free (it’s a free software, under the GPL).

Waiting for an internet of things for everybody

Sun, 11 Dec 2011 23:42:41 +0000

There are a few days left to vote for the Internet of Things Awards 2011. Initially I thought it was a very good thing, with lots of nice ideas for the future. But then I felt something was missing, imho of course: practical projects that will help the remaining 5 billion people who are not affected by that internet of things as it currently is. Let me explain …

TEDxBrussels in tweets and videos

Wed, 23 Nov 2011 23:10:57 +0000

TEDxBrussels is a local, self-organized event that brings a TED-like experience to Brussels. I already often mentioned videos and presentations from TED (for instance here, here or here). When I read that it will again be organized in Brussels in 2011 I decided to attend this edition. Here is a short summary of this intense day with my tweets and the just-released videos. It would be very time consuming to write about each and every talk. Here I will just highlight speakers I like the most (you can have a look at TEDxBrussels website for the complete list of speakers).

Google+ API started

Thu, 15 Sep 2011 23:19:34 +0000

Google+ (G+) is a social networking and identity service operated by Google. It started a few months ago like a closed service from where you can’t get out any data and where the only possible interaction (read/write/play) is only possible via the official interfaces (i.e. the web and android clients). Google promised to release a public API and it partly did so tonight, here.

As they stated, “this initial API release is focused on public data only — it lets you read information that people have shared publicly on Google+” (emphasis is mine). So you can already take most of your data out of G+ (note that it was already possible to download your G+ stream with Takeout from the Google Data Liberation Front). As usual, it’s a RESTful API with OAuth authorization. It comes with its own rules and terms (it could be interesting to add to GooDiff). The next step would be to be able to directly write something on Google+.

Reference Manager 10 with Wine

Wed, 14 Sep 2011 21:20:43 +0000

Reference Manager is a commercial reference management software package. It is extensively used in biomedical research, along with Endnote (sold by the same company), mainly because the main OS in these labs is Windows from Microsoft. I used it at the university and still have some reference databases in its format (with file extension .rmd).

This evening, I had to go back into one of those proprietary, closed databases I still had (most of my references were later re-entered in a BibTeX file). I could have borrowed my wife’s computer running Windows or tried some Open Source software that can open .rmd files. But it would have been too easy. So I tried it with Wine, a program that allows Microsoft Windows applications to run under Linux. In Wine AppDB, it is written people had tried version 9 and 11. In the old time, I bought a student license for version 10.

Adobe Flash Player update: qui fait le malin tombe dans le ravin

Wed, 07 Sep 2011 20:37:36 +0000

This well-known French proverb is similar to: “pride comes before a fall”.

This evening I was told by the newly installed version of Firefox that my Flash player was outdated. Firefox provides a simple link to download that Flash Player. I save the installer (install_flashplayer10_mssd_aih.exe) in a directory where I save all my downloads before sorting them. I launch the installer. It moves itself to my system temporary directory and launches itself again. First I find it very rude from the installer to move itself anywhere on my disk. Then now, since 15 minutes it’s stuck at the step where it tries “retrieving install”.

We don't need a computer at home

Wed, 03 Aug 2011 01:03:00 +0000

Historically, computers were invented to solve issues in the factory or the office (university office or company office) but recently invaded home and are becoming ubiquitous.

At the beginning of this invasion, computers for home were (and are still) very similar to the ones for the industry/office: a CPU, a keyboard to enter data or commands and a screen to see what was happening. Artifacts to be attached to the computer were first invented for the corporate world and then progressively entered into homes. I still remember the first mouse we had at home: it was like a mini-revolution. After years there were still some software that could not take advantage of it or its usage was implemented but in a rudimentary way. Idem for the first webcam we acquired: only the provided software was able to use it. Now it comes embedded in most computer screen and can be used for various purposes (video chat, take pictures, read bar codes, art, …).

OS need an immune system and not a CDC-like

Sat, 23 Jul 2011 01:15:30 +0000

In an IT World article, Tom Henderson gives many details about a US-government-led CDC-like organisation to fight malware. In summary, he states that companies and consultants providing security and prevention around operating systems don’t have any real motivation to eradicate malware. And in case of an “outbreak” of these malware, he added one needs a US government body to look after every computer “health”, coordinate the surveillance and the response. He even pushes the comparison with the human medical system by introducing a Hippocratic Oath for computer healthcare.

Managing photos

Sun, 15 May 2011 16:22:42 +0000

I am still managing my photos based on directories named by date + event (e.g. “110515-person” contains photos from the person and taken today). I tried Shotwell, saw Picasa or iPhoto working but I was not really convinced. Maybe I like to be closer to the file structure (and it’s enough for my needs) and don’t like too much the idea of being dependent on a software and its internal database.

R and the proxy server

Tue, 29 Mar 2011 15:35:17 +0000

R is a " a free software environment for statistical computing and graphics". Being a desktop software, R is working out-of-the-box, even if you don’t have a network connection. However, if you want to install packages using a repository on the internet, you need a network connection (of course). If your computer happens to be behind a proxy server, you have to slightly modify your shortcut (in MS-Windows) to allow R to download packages. This can be done by modifying the “Target” field in the “Shortcut” tab of the shortcut properties (right-click on the shortcut to R, select tab “Shortcut”, edit field “Target”):

What is my proxy on Windows XP?

Tue, 29 Mar 2011 15:24:27 +0000

" In computer networks, a proxy server is a server (a computer system or an application) that acts as an intermediary for requests from clients seeking resources from other servers." From Wikipedia. This can be useful for a company to force its employees to use a proxy (to filter where they surf, to cache the web content for speed issues, to keep machines on the network anonymous, etc.). This post will look at 3 ways to get the proxy definition for a Windows XP machine in order to use that information in another program. It may work in other Windows-type operating systems.

Is there a life after delicious?

Wed, 29 Dec 2010 00:12:21 +0000

Delicious is " a social bookmarking service that allows users to tag, save, manage and share web pages from a centralized source. With emphasis on the power of the community, Delicious greatly improves how people discover, remember and share on the Internet". I extensively use(d) it and I think it’s one of the very good tools Yahoo! (its parent company) has to offer on the web for the moment (along with Flickr and the currency converter). I was thus very disappointed to read persisting rumours that Yahoo! will shut down Delicious. And I’m not totally reassured by the official comment from the Delicious blog: " No, we are not shutting down Delicious. While we have determined that there is not a strategic fit at Yahoo!, we believe there is a ideal home for Delicious outside of the company where it can be resourced to the level where it can be competitive".

Installing Fedora 14 on a Toshiba Satellite L670-10K

Wed, 10 Nov 2010 01:12:05 +0000

No issue, installation even smoother than the installation of Fedora 13 on the same machine, last month.

Installing Fedora 13 on a Toshiba Satellite L670-10K

Thu, 21 Oct 2010 23:31:15 +0000

I quickly needed a new laptop to continue working and I found a Toshiba Satellite L670-10K. It’s a nice entry-level laptop with a dual core processor (I didn’t know Intel was still doing Pentium-branded processors) and a 17" screen ( read the specs for other details). I downloaded the latest Fedora Linux (version 13, 64 bits ; and version 14 is coming soon) and installed it from the LiveCD. Nearly everything was recognized out-of-the-box: screen resolution, graphical card (Intel, with 3D effects), wired network, webcam, card reader, sound card, etc.

A good issue of Nature, obviously!

Tue, 19 Oct 2010 23:12:26 +0000

The October 14th, 2010 issue of Nature is obviously a good one. It had to be a good one! I usually advocate Open Access but it is always nice to reading complimentary issues of Nature which is Closed Access but is also publishing very good articles about science at the same time.

In this issue, I was interested in various topics …

First, there is a serie of articles about the US midterm elections and what (US) scientists feel about two years of Obama administration. Obama promised total transparency in American science, a new era of integrity and more freedom for scientists. From what I read, this isn’t the case yet.

Facebook updates: nothing to fuss about

Fri, 08 Oct 2010 00:16:58 +0000

So Facebook, the current paramount social website, updated its website with the possibility to download all your data (among other updates). I don’t see why people need to fuss about this.

Although maybe useful, the important is not to be able to retrieve your data. After all, if your pictures are on Facebook, they were previously on your computer / camera / whatever. So you should already have them (and Facebook sends them to you in a zip file? what a feature!). Unless Facebook allows you to also download data about you but uploaded by others; this is a bit more interesting from a sociological / academic point of view (what has been posted about you). And then? A “big” step towards interoperability between social websites? Are you joking? For interoperability, you need 2 partners and, to my knowledge, no other websites (social or not) are currently offering the possibility to upload data from Facebook. Will it arrive? I’m sure of it. Is it secure? I doubt it: nothing is 100% secure in IT, Facebook is no exception. But this is still not important!

Llinking two recent posts seen elsewhere

Tue, 03 Aug 2010 19:20:31 +0000

Namechk.com ( Check Username Availability at Multiple Social Networking Sites) bookmarked on delicious.com by Philippe
" one possible use of the Facebook profile information: generating a good dictionary from fabebook-names-original.txt to brute-force password" seen on Twitter.com/adulau

Now use Namechk to find all combinations of >= 2 letters used on more than 1 service. I guess there is a high probability that two identical username strings on two different services belong to the same physical person. Look at their profile/activities/pages/whatever on the various websites, you have now a wonderfull network of knowledge about these people. I also guess that if a flaw is discovered in one of these services that allows to recover users passwords, you could use the same password on all the other services for the same username.

Tetris wall

Tue, 20 Jul 2010 21:59:34 +0000

Dear wife,

I agree to have the decoration you want everywhere in our new home. You can have all the furniture and appliances you want in the kitchen. I’m OK if all the shelves with my computer books are in the basement. OK too if you don’t want to see the file server in the living room. Agreed: I’ll put back Windows on your laptop. But …

But I absolutely want one wall painted like these:

Bittorrent used to deploy updates

Tue, 20 Jul 2010 20:49:24 +0000

I just watched a video from Larry Gadea working at Twitter: Twitter - Murder Bittorrent Deploy System (speaking at CUSEC 2010).

Briefly, the problem Twitter was facing was the deployment of updates to thousands of servers in a short amount of time and dealing with errors (broken servers, e.g.). A nice, simple, cool and free way of solving this issue was to use the Bittorrent protocol (via Python and a stack of other free software) to actually deploy updates. In summary, you go from a unique repository facing thousands requests approximately at the same time:

Network bandwidth during lecture

Wed, 30 Jun 2010 17:34:36 +0000

One of the differences between university lectures in Belgium and in the United States of America is that, in the US, most of the students are carefully “listening” to the lecture while having their laptop on and connected to the internet. I didn’t departed from this custom :-)

Yesterday, I was trying to download a Linux DVD (that’s what university networks are for, isn’t it?) and observed an interesting pattern in the network speed during the lecture. If I assume that the total bandwidth available remains constant, the one available to me was drastically reduced as the lecture was going on.

Welcome PDF comments in Evince!

Sat, 30 Jan 2010 22:52:24 +0000

Three months ago, I complained about the fact we can’t see comments made in PDF files in Evince. With a recent update to Fedora Core 12, Evince was also updated to version 2.28.2 and, among many improvements, comments ( annotations) added to PDF files are now visible :-)

Bye, bye, Adobe Acrobat Reader ;-)

iPrison

Fri, 29 Jan 2010 11:50:04 +0000

Frankly speaking, I don’t really understand the passion for the new Apple iPad (an " iPhone on steroids"?). It’s a beautiful-looking machine but it also jails its user in the “Apple ecosystem”. It’s just consumerism.

Apple has a record of launching beautiful-looking devices and shiny products. In the beginning of the years 1980s, they popularized the computer mouse and the graphical user interfaces as we know them today. In the beginning, one would love the simplicity of use of Apple computers and software, especially compared to the MS-Windows or GNU/Linux versions at that time (I’m speaking of the years 1990s). The end-user was then at the center of the “computer experience”. But now, it seems the end-user becomes a (paying) consumer, nothing else.

3DSecure not secure

Thu, 28 Jan 2010 22:51:59 +0000

You may have seen in various places that “3-D Secure” (aka “Verified by Visa” or “Mastercard Securecode”) is not as secure as it says. The original paper is here (PDF).

Unfortunately, having implemented the 3-D Secure system via a third-party somewhere in Europe, I have to agree with the authors. I will insist here on one aspect - the inline frame - but the authors are giving more aspects and some solutions worth considering in their paper.

Waiting for PDF comments in Evince

Sun, 11 Oct 2009 21:51:03 +0000

Evince defines itself as “simply a document viewer” (for Linux/Gnome and now for Windows too). However it can already read a lot of formats: PDF, TIFF, PS, DVI, DJvu and plans to support a lot more in the future.

But for me there is one important feature missing: the ability to read comments in PDF files. I sent PDF versions of draft documents to my PhD thesis promoters and they send them back with their comments. Open them in Evince: you’ll only get the balloons but no possibility to click on them (see Figure 1 below). Open them in Acrobat Reader and not only you can see that there are comments but you can also see their content (see Figure 2 below).

postr, simply puts your pictures on Flickr

Mon, 14 Sep 2009 21:26:53 +0000

I really like gthumb to have a look at my photos, quickly perform some basic modifications or effects and display all the photos to people around me. But there is one thing that is annoying me: it seems impossible for my gthumb version (2.10.11) to upload to Flickr, where I put some of my pictures. There is an " issue 73" in the GNOME’s GHOP Contest page from 2007 and the development seems to be done ; it’s just not yet in the main branch.

Revision control software migration question

Sun, 13 Sep 2009 22:37:25 +0000

In software development (as in many other fields, like paper or thesis writing ;-)), you often need a revision control software to effectively manage all the changes made to your source code (or sections and chapters). It’s even more important if you work with other people on the same files, on different versions of the same sources, with people in different locations and with different systems.

The problem I currently try to solve (or, at least, try to bring a solution to) is the following … The system doesn’t initially use any revision control software. People are able to edit any file they want, one at a time (file locking which is very annoying). Basically, there is only one version of a file per project: the current one. If another project tries to merge the same file from another project, someone has to manually review all the lines in order to see what should remain and what should be left. In order to reach a previous version of a file, you have to manually remove lines marked with the patch reference at a specific location on some lines (it does work in some programming languages and not at all in all others). In fact, a rudimentary revision control system exists but it’s completely outside the development environment. When a file is modified, it’s name is entered in a “patch system” with the reason why it was modified (when you are lucky). If you forget to enter its name, the system can’t do anything for you (since it’s not aware of anything).

Wordpress problem with permalinks after upgrade

Mon, 10 Aug 2009 19:20:21 +0000

If you get error 404 with your permalinks and RSS feed after an upgrade of your Wordpress installation to version 2.8.3, it’s worth to check the “Permalinks” section (under the “Settings” tab in the admin panel). Try set it up to “Common”, save changes and then put it back to your previous structure (“Month and name” in my case). This should solve most of current 404 errors after upgrade. If not, check the Wordpress support forum.

Installing Pwytter on Fedora 11

Sat, 08 Aug 2009 10:12:38 +0000

This morning, it was impossible to post tweets on Twitter so I finally gave in to install a Twitter client. Amongst many software available, Pwytter seemed interesting to try: free software, written in Python were my two criteria.

Unfortunately, the installation process is not straightforward (although its use of the general python setup procedure). Here is how to install it on Fedora 11 from the command line:

Download Pwytter, unzip it, enter directory pwytter-0.8
Install ImageTK: as root, type " yum install python-imaging-tk" ( in Fedora, ImageTK was renamed python-imaging-tk)
Install simplejson: as root, type " yum install python-simplejson"
(optional) launch: python setup.py build
launch: python setup.py install
Complete the installation by copying some files with the 4 lines below (type them as root too) ( a comment in pwytter blog helps to solve the pwCache installation bug):

cp pwCache.py /usr/lib/python2.6/site-packages/pwytter-0.8-py2.6.egg
cp pwCache.pyc /usr/lib/python2.6/site-packages/pwytter-0.8-py2.6.egg
cp -r media/ /usr/lib/python2.6/site-packages/pwytter-0.8-py2.6.egg
cp -r theme/ /usr/lib/python2.6/site-packages/pwytter-0.8-py2.6.egg

Now you can launch pwytter from any user! In addition, since the source code is available and Identi.ca supports a Twitter-compatible API, let’s see if it’s easy to modify pwytter for Identi.ca :-)

Live picture from the Bruxelles Grand Place

Sat, 16 May 2009 19:15:32 +0000

On the Bruxelles website, you can watch from and move a webcam on the Grand Place. The resolution is good enough to distinguish faces in you zoom. But what is more interesting (imho), is that the stream from the webcam is just a stream of still images from http://www.brucity.be/webcam.jpg. The image below was the current image from the webcam when you loaded this page ; reload the page to see another picture …

March 25th, 2009: Document Freedom Day

Tue, 24 Mar 2009 22:01:14 +0000

This 25th of March, 2009 is Document Freedom Day. Although it’s not as important as starvation in parts of the world, the economic crisis or the continuous deterioration of our privacy and civil rights (in UK and elsewhere), it’s good to take a break and think about our use of electronic documents in our everyday live. Let me just give you an example …

A few days ago, I was trying to retrieve data from an experiment. As a well-formatted student, I stored my data in a then state-of-the-art, proprietary statistical software my dear statistical professor taught me to use. As long as I had this software, it was fine. Now that my university stopped to pay the license, that I didn’t installed this software on my new computer, I am stuck with a serie of 1, 0 and other delirious characters in that file. Does that mean I lost all my data? Yes.

Some useful software for programmers stuck on MS-Windows

Mon, 23 Mar 2009 22:23:24 +0000

Sometimes, even if you mainly develop on Unix/Linux boxes, you are stuck with MS-Windows on your desktop. Moreover, although your are a developer (i.e. someone who is supposed to know how to run a computer), you have no administrator rights so you can’t install the right tools that can improve your productivity and enhance your code stability/security. This is for the sad part.

Fortunately, Free Software are there and most of them can even be run without being installed on your machine, just copy the software and use it! Here is a list of some of the software I’m using. Feel free to promote your favourite application in the comments.

Welcome again!

Sat, 28 Feb 2009 14:31:28 +0000

Hi, and welcome back on my blog.

Following the progressive migration from epot.org to jepoirrier.net, you landed on the new address for my blog: http://www.jepoirrier.net/blog ( new RSS feed here).

The migration process was easy, thanks to the WordPress eXtended RSS that contains posts, pages, comments, custom fields, categories, and tags. But there are two things left I wanted to keep: existing users and images which links are hard-coded in various posts.

FOSDEM 2009 and Gemvid 0.6c

Sun, 08 Feb 2009 00:01:02 +0000

This year, I only went for the Saturday afternoon session of FOSDEM 2009, the Free and Open Source software developers’ European Meeting. Two years ago, I mentioned the general trend that more women were interested in free/open source software/movement and this trend continues. But this time, I also noticed some really cute babies … and my son Neel-Alexandre was one of them of course! Although he’s only 7-month-old, he was really interested in the FreeBSD, Linux and Firefox mascots (respectively a red daemon, Tux the penguin and a fox). You are never too young to taste the truth ;-)

Baby movements during sleep

Tue, 27 Jan 2009 23:39:11 +0000

After a while, here is why I got a TV tuner for my Linux laptop, took screen captures and wrote a script to add a timestamp on pictures … I wanted to know how my (then 5-month-old) son was sleeping (his mom can be reassured: I was not planning to put electrodes on his scalp ;-) ).

Get the Flash Player to see this player.

var s1 = new SWFObject("../videos/player.swf",“ply”,“360”,“240”,“9”,"#FFFFFF"); s1.addParam(“allowfullscreen”,“false”); s1.addParam(“allowscriptaccess”,“sameDomain”); s1.addParam(“flashvars”,“file=../videos/081129-night.flv&image=../videos/081129-night.jpg”); s1.write(“container”);

Fosdem 2009, February 7-8th

Sun, 11 Jan 2009 16:04:43 +0000

Fosdem is “a two-day event organized by volunteers to promote the widespread use of Free and Open Source software”. I will be presenting Gemvid during a lightning talk on Saturday :-)

Awk oneliner to find a string in text files

Mon, 01 Dec 2008 22:00:08 +0000

If you want to know the name of files containing a special string, grep -c is your friend. But you also get names of files not containing your string (with count = 0). If you only want the names of files containing “mystring”, awk can help you:

grep -c "mystring" * | awk ' !/:0/ '

And if you don’t even want the number of times “mystring” appears (on 1 line):

Bad choice for France Télévision web platform

Mon, 21 Jul 2008 16:20:46 +0000

It’s sad to see France Télévision chose a proprietary platform (MS Silverlight) to develop its web platform for video delivery … They developed this “thing” with public money; the content should at least be available to all the public eyes (even the “without Silverlight” link requires to have Windows Media Player 11 which even recent MS-Windows PCs do not have).

Here are some general reasons why it’s a bad idea to develop something with Silverlight:

Firefox 3.0 + Flash on a protected Windows PC

Sun, 22 Jun 2008 17:40:17 +0000

Very often, your company doesn’t allow you to install a new software on your company computer. For this purpose, Portable Apps is a very interesting website: it contains a lot of free software ready to be used, without any installation process. Moreover, it releases latest version of software very quickly. For example, 1 or 2 days after the launch of Mozilla Firefox 3.0, it was already in Portable Apps.

Most Firefox plugins (" add-ons") can be installed in the Portable apps version of Firefox, but not all of them. The Adobe Flash plugin is one of the few ones that you can’t install without administrator rights …

Comment your code

Mon, 09 Jun 2008 20:36:06 +0000

It doesn’t matter if you write proprietary or open source code, comments in your code are very important (somehow even more important than readability and functional correspondence to the client’s needs). This is especially true if someone else is supposed or will, one day, look at your code, re-use your code and/or build upon your code.

For example, despite the fact that this source code header explained what the whole source is doing, you can’t tell what processing is done in this paragraph:

I can't read my blog

Mon, 02 Jun 2008 22:47:36 +0000

At least from my office. Sadly true ;-) since one of the rules of my company proxy server bans all URLs with the letters “blog” inside (no blogger.com, blogspot, … websites either). Fortunately, there are a lot of web-based feed aggregators (which are not – not yet? – banned). It also blocks all URLs with the “exe” string so we are not able to visit the Belgian Post website (it uses an URL containing “outletlocator.exe”) ; I didn’t find any bypass yet.

Two nice schemes about Open Source

Sun, 13 Apr 2008 22:04:22 +0000

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).

"Word processors" are not meant to be usable

Thu, 20 Mar 2008 23:03:01 +0000

(… at least for large documents)

Two week-ends ago, I spend a whole day trying to apply a consistent style to a thesis. I spent hours trying to be obeyed by a word processor because it would systematically change the style of some element, somewhere in the 100-or-so pages. Including figures was also a nightmare: we had to keep an eye on the (limited) memory of the computer (otherwise we got unexpected screen freeze, a lot of noise from the hard disk (paging), etc). Generating a bibliography was also another daunting task, even with the use of a dedicated reference manager …

Vertical badge

Wed, 07 Nov 2007 20:13:48 +0000

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).

How many days without governement?

Tue, 06 Nov 2007 00:00:37 +0000

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) ;-)

OpenSocial, a step further towards a "society of social networks"

Sun, 04 Nov 2007 12:24:27 +0000

Since Thursday, Google Code is hosting the OpenSocial project, a group of APIs allowing the development of common software for a certain number of “social networking” websites (e.g. LinkedIn, MySpace, Ning, Orkut, …).

Before Thursday, every programmer wanting to develop a software for social networks had to learn an API, how to write code and sometimes a new language for each of these networks (when these ones exposed a public API!). Now, OpenSocial gives access to the most common functions of all the participating networks. Currently, the API gives access to:

Beaming Multimedia Solutions Ltd

Sun, 08 Jul 2007 16:20:58 +0000

Congratulations to Ananda for the creation of his company, Beaming Multimedia Solutions Ltd.! This guy is like an example to follow when you strongly believe in one idea and really do everything to achieve it … Congratulations again!

Domain name is registered but website is not yet active.

Snownews

Wed, 20 Jun 2007 05:52:02 +0000

Taking advantage of my laptop crash, I went back to some text-mode tools ( vim, mutt, …): they are fast, easy to use (once you read at least the introduction section in the manual) and reliable (text files are more easily recovered after corruption than binary blobs). I also tested and adopted Snownews.

Snownews is a text-mode RSS newsreader. Installing it is very easy: download the archive, and type the usual “./configure; make; make install”. Since I’m following some blogs written in French, I configured Snownews with Unicode support: “./configure –charset=UTF-8”.

A voté !

Sun, 10 Jun 2007 11:55:14 +0000

As every Belgian citizen, I voted today for our legislative bodies ( Chambre et Sénat). As always, I was confronted to the same problem: electronic voting. Technically, I’ve no problem to understand and use the system: it’s an ethical problem. I don’t know if my vote is correctly written on the card, even with all the given guarantees and technical details (you can test such a voting machine here or watch a demo of the Belgian system, both in French). Personally, I saw two problems:

Another reason why free software matters

Wed, 09 May 2007 12:18:34 +0000

This morning, I read Tim Anderson’s " Why Microsoft abandoned Visual Basic 6.0 in favour of Visual Basic .NET". While reading his article, I only had one idea in mind: this is another example of the importance of free and open source software. If you are not a programmer, you don’t need to read the remainder of this post; software users have many other reasons to prefer free software over closed-source software (but it’s not the subject of this post).

Under attack

Sun, 08 Apr 2007 14:07:22 +0000

Short message for spammers: you lose your time trying to add irrelevant comments on this blog since no comment is published before I agree so. Moreover, I activated Akismet spam filter since this morning

… But I doubt spam robots read notices where they put spam comments.

Although I disallowed comments (and even pings) on some posts, I felt something strange this morning: more and more comments had to be moderated on this blog. By default, no comment are directly published. If the comment is relevant (even if the author has a different opinion than mine), I publish the comment (1 click). Otherwise, I delete the comment (another click) and disallow comments and pings (human contributors can still send me their comments by e-mail and I’ll publish them). From 1.50pm to 2.50pm (some minutes ago), I received 153 spam comments. Sorry guys, unless you found a serious flaw in this blog engine, comments will still be moderated by a human who dislike spam.

Unlimited storage in online apps

Wed, 28 Mar 2007 05:00:41 +0000

Although I liked Bill Burnham’s post about the " storage explosion" I think he forgot one thing in one of his last posts. In " YahooMail, Storage, and the Battle For Personal Data" he explains the announcement of unlimited e-mail storage for free by Yahoo! is the indication of two trends: for him, the obvious one is that storage is cheap and the less-obvious trend is that there will be a battle to control the user data in such “web applications”.

About iPod+DRM

Mon, 12 Mar 2007 11:11:18 +0000

I don’t understand why people are buying and offering Apple iPods to their family members. In fact, offering an iPod is like telling you: “Here is a costly electronic device I’m giving you, it’s cool thanks to huge marketing efforts but hey, in 5 - 10 years (or immediately if you lose your player), you won’t be able to read any music files you bought anymore: it has DRM inside. Moreover, when this one will be old, you’ll be forced to buy an Apple player to keep listening to music you bought”. In short: “I am offering you a beautiful trap”.

A small journey in the world of LiveCDs

Fri, 02 Mar 2007 22:50:51 +0000

I have plenty of other things to do but, this evening, I decided to stop a little bit and try some LiveCDs I freely got at Fosdem. Since I did it very quickly and was tired, don’t take what I wrote for granted: LiveCDs are there to be tested. Download one and test it by yourself!

The first LiveCDs I tried were derived from Sun OpenSolaris (and on the OpenSolaris starter kit DVD). BeleniX was quite cute, directly launching XFCE. Quite a few applications were there. Some refresh problems were also present in the console. An old USB key was recognised without problem, as most parts of my low-end workstation.

Links to some interesting documents

Wed, 10 Jan 2007 20:49:17 +0000

Some interesting links for today (didn’t had time to read everything, that’s why I’m storing them here):

Java boutique has a in-depth review of NetBeans 5.5
Java Practises has a small tip about implementing toString in Java
A new (very important ;-) ) feature of Java 6: the splash-screen functionality. Another interesting thing is that Java DB (Derby) is integrated by default.
About databases, David Coldrick’s Weblog hosts an interesting discussion about H2 -vs- Derby databases
The Java Plug-in Framework Project
Besides Design Patterns, OpenSubsystems released the Open Patterns, a repository of common application functionality patterns …

Some links about companies:

Ruby France logo proposals

Tue, 28 Nov 2006 01:40:41 +0000

I couldn’t find sleep tonight (*) so I did two small variations on the Ruby official logo for Ruby France, since they are looking for a new logo (**). Double-clic to enlarge, single-clic to reduce back to the small images (***) :

I also like Greg’s proposal.

(*) it happens very often these days
(**) No, I don’t know Ruby
(***) Doesn’t work if javascript isn’t enabled in your browser (usually it is) + Internet Explorer doesn’t correctly render the transparency ; please use a real browser instead

Dry beveling micropipettes using a computer hard drive

Tue, 31 Oct 2006 14:41:22 +0000

I really like this kind of application: a person used an old hard disk to bevel micropipettes for electrophysiology [1]. It’s fast, simple, easy and the author got an article published at an impact factor 1.784.

[1] Canfield, J.G. " Dry beveling micropipettes using a computer hard drive" Journal of Neuroscience Methods 158 (1):19-21.

Looking for a good free UML2 modelling editor ...

Wed, 04 Oct 2006 22:38:12 +0000

I was using Poseidon as a modelling editor for my UML2 diagrams. It was based on Java and I was able to run it from both GNU/Linux and MS-Windows. It was not free software but the Community Edition was free (as in “free beer”) and has all the tools I modestly needed. The only trick: all the diagrams had a string in the bottom, stating it was not meant to be used for commercial purpose (for educational purpose, I’ve written a small software that removes it).

Lightweight installation of computer

Wed, 06 Sep 2006 23:51:10 +0000

This evening, I prepared a computer for the lab. Don’t blame me but it has to be under MS-Windows and with MS-Office. Knowing it’s only an Intel Pentium II MMX (“x86 Family 5 Model 4 Stepping 3”) with 64Mb of RAM and 2.4Gb of hard disk, I needed to find general software that has the smallest footprint in terms of both memory and hard disk consumption. Here is a small list of software I found interesting (mainly for me to remember):

I really like LaTeX Beamer

Thu, 20 Apr 2006 01:26:45 +0000

As I previously wrote, I’ve discovered the Beamer class for LaTeX some months ago and I really like it! It’s very easy and straightforward to use (provided you know a little bit of LaTeX, of course). I’ve also noticed it forces me to actually prepare my slides and illustrations before beginning to create the slide show. This is a good point since 1) it forces me to stress the structure (rather than doing it as one goes along the slides) and 2) it allows me an easier and better re-use of illustrations and slides previously shown (in Powerpoint or Impress, you had to think of what objects you have to copy ; here, you have only text to copy).

A new Jabber ID

Tue, 18 Apr 2006 23:06:47 +0000

I’ve recently learned that the Jabber.org server was an experimental one but I was too lazy to change my Jabber ID. Now that the Jabber.org server is down (apparently since 23.00, Belgian time), I am forced to change. My new Jabber ID is “jepoirrier at jabber.fr”. I will still use the old one (“jepoirrier at jabber.org”) but I will gradually switch all my contacts to this new ID.

BTW, the Jabber.org status can be found here. The Jabber.fr server is hosted by APINC and its status are here.

Very small Bash scripts to retrieve multiple PDF and create a book

Mon, 20 Mar 2006 16:21:40 +0000

The National Academies Press are putting some of their books on-line. I was particularly interested in the Guidelines for the Care and Use of Mammals in Neuroscience and Behavioral Research. The only “trick” is that they provide the book one page at a time (either in HTML or in PDF format). If you want entire chapters or the whole book in one file, you have to purchase it. I think it is a fair deal (how many publishers do that?).

Available for GNU/Linux and MacOS but not for Windows

Wed, 15 Mar 2006 14:42:28 +0000

Although a lot of software is available for GNU/Linux and not for Windows, I am always happy to see new ones developed for GNU/Linux but not for Windows (at least not yet). One last example: Zfone. This software “intercepts and filters all the VoIP packets as they go in and out of the machine, and secures the call on the fly”. The public beta version is already available for GNU/Linux and MacOS. Windows version will be available in mid-April (only). It would be great if Philip Zimmermann releases the source code under a free software licence ( other comments and ideas in this Slashdot news).

Getting rid of old hardware at work

Mon, 13 Mar 2006 23:28:40 +0000

Today was the last day to get rid of all the old computers and electronic devices we could “store” in our lab. As you can see below, they are mainly broken screens …

SMC wireless card recognized automatically on a FC4

Sun, 05 Mar 2006 01:30:23 +0000

Since I moved my desk in another room far from the ethernet plugs, I needed a wireless access to the laboratory network (and internet). I tested two PCMCIA card on a laptop with Fedora Core 4.

The first card I found at home was an Acer card without too much information on it (it was sold with my wife’s laptop). When inserted, a lspci tells me that it’s a Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8180L 802.11b MAC (rev 20). But the Fedora Hardware Browser doesn’t recognize it. There is an open project to support this card but it’s still experimental ( they are saying it on their own webpage). My lazy nature asked my hand to eject the card. This card is recognized but not working ‘out-of-the-box’.

Yes, Trusted Computing is used for DRM

Sun, 19 Feb 2006 14:41:18 +0000

In this blog, Andy Dornan takes us from a simple demonstration of Lenovo laptops new “abilities” to the fact that the real owner of documents with DRM is the software company and not the owner/creator of the document.

You can create a document and claim ownership on it with DRM systems. Unless you can open it with or export it to a software coming from another company, you’ll be dependent on one company to open your document. Imagine you create a text file and protect it with sofware X. If you cannot open it in another text processor/editor and that the maker of X decides that you cannot open your document anymore (for whatever reason: you live in a dangerous “terrorist” country, your name sounds too different, you didn’t pay your monthly fee on time, etc.), your are stuck.

MS-Visual Studio 2005 for Indians and Asians? :-)

Tue, 14 Feb 2006 00:23:11 +0000

I installed MS-Visual Studio 2005 this evening (I had to). The installation took around one hour. During this time, three persons are telling you the new tools and advantages integrated in their product. One is Indian and the two others are Asians. With a Vietnamese mother and an Indian wife, it’s a strange feeling when an occidental product takes Asians to advertise their product.

(Well, even if you are not Indian nor Asian, you can still use VS2005 ; it’s just a post at 00:21)

And I thought I had stress before my presentations ...

Sat, 07 Jan 2006 22:18:55 +0000

There is a story on how Steve Jobs prepares his talks for Apple’s keynotes in the Guardian Unlimited. Well, it doesn’t say much about the preparation in itself. But I can feel the stress Mike Evangelist is experiencing: he had to talk in front of hundreds of people, in front of his boss and present software not yet finished. And I thought I had stress before my presentations …

Of course, there is another reading of this article. OK, Apple is a small technology company. But it developped a good sense of communication. When you are buying an ipod, your are not only buying a portable music player (btw including imprisoning DRM): you are also buying a feeling (of hype, of having the last gadget, …). When you are buying a Mac computer, it’s also a feeling of being part of “another” community, … Apple cultivated this feeling since the beginning with slogans like “Think Different”. And, of course, this article, the book Mr Evangelist is trying to write, … even this post on this blog, they all participate in the “buzz” around Apple keynotes. Finally, if this noise (*) wasn’t there, Apple will only be another computer-selling company.

Strange things with Poseidon for UML 4.0

Mon, 19 Dec 2005 00:18:45 +0000

Gentleware recently released version 4 of “Poseidon for UML” (an UML modeling tool). They said it now respects many more features of UML2 but I am not proficient enough in UML to clearly see all the advantages. But there are still some strange things. Two examples:

1. The default graphics format of Poseidon installed on a Fedora Core 3 is PNG. The default graphics format of Poseidon installed on a Fedora Core 4 is JPG (same with SuSE). I tried to look in the config files (in fact, in all text files in the installation path) but I didn’t find anything related to this topic. It’s probably an OS default setting but I didn’t had the time to check.

My webcam is working (again)!

Sun, 11 Dec 2005 02:28:48 +0000

My webcam is finally working with Fedora Core 3. Thanks to Luc Saillard’s page on Philips USB Webcam Driver for Linux, I was able to download and put a new module for my webcam (a Logitech Quickcam Pro 4000). I first tested it with GnomeMeeting and it worked fine. Thanks to camE, I was able to take this snapshot (and get rid of any unnecessary GUI ; snapshot is a reduced version of what I get).

Looking for C/C++ free source code?

Mon, 05 Dec 2005 23:19:07 +0000

If you are looking for free (as in ``free speech") C/C++ source code, csourcesearch.net could be interesting for you. Apparently, Robert Schultz spent one year using various tools to enter millions of lines of C/C++ code from free software in a database. Most of the code come from software under GPL (more than 40% ; see all the licences parsed and all the packages used). And results are color-coded for the pleasure of your eyes.

What is Grid Computing?

Mon, 21 Nov 2005 06:09:02 +0000

I’ve recently discovered that a grid computing service was available at the University of Liege (where I am working), inside the Alma-Grid structure. The “Alma-grid” name is quite confusing since, if I understand correctly, they offer lab solutions for genomics, proteomics, etc., and bioinformatics is only a part of it.

A Grid is a network of many computers sharing their unused ressources (CPU and/or disk storage) to solve large-scale computation problems. We can see that like a distributed computational and/or storage system. Well-known “grid computing” projects are, a.o., SETI@Home or Folding@Home. The main advantage of a grid is that you reach the power of mainframe computers in terms of CPU power and/or storage, without the cost of buying one since a grid usually uses common desktop computers distributed around the world.

Some links, after the week-end

Sun, 20 Nov 2005 22:40:30 +0000

The Linux Distribution Chooser: after a kind of survey, they give you a Linux distribution that can suit you. In my case, they were right since they gave me the advice to use the Fedora Core (that I am currently using).
Booh, a static Web-Album generator (a French news from the author)
CImg, a C++ template image processing library
Do-it-yourself LED lightning for the house
The Warning label generator :-)

During this week-end, I’ve met a lot of people but I didn’t worked a lot (and my boss is asking for some results asap …).

Some news from the free VoIP world

Wed, 16 Nov 2005 22:39:55 +0000

Here are some evening news … While surfing on Slashdot and LinuxFr, I read two articles on yakforfree and openwengo. Yakforfree claims to bring the revolution to your voice communications by adding video. Of course, their main competitor - Skype - doesn’t offer it yet. But video conferencing software are already available since quite some time, and some of them are even free (as in free speech): gnomemeeting, e.g. OpenWengo is open source (GPL), backed by a French telecom company and offer voice, video and chat communications between PCs (MS-Windows and GNU/Linux). It is said to work on the open SIP protocol (I am wondering if one can contact a Wengo user with another Sip-based software). And, for the moment, they offer a 3 euros communication credit for every inscription (I suppose it’s for calling regular phone lines). Hmmm … seems interesting. If I have time, I’ll try it.

I am a statistic

Fri, 22 Jul 2005 16:53:07 +0000

I am a statistics because I replied to this MIT weblog survey (I found the link on Alex Schroeder’s diary). Alex Schroeder put the “I made some Science” sticker on his weblog but, since I did some biological experiments today, this sticker wouldn’t mean anything on my website ;-)