I have been on leave for a couple of days and today when I booted my laptop the openSUSE updater notified me of 4 security updates. While I was watching zypper updating the system (I prefer the command line client) I wondered if it would be possible for zypper to download and install patches/programs/etc asynchronously.  To explain better: instead of downloading a patch and then installing it, why can’t zypper download the patch and then start a process/tread to install it while it immediately starts to download the next file ? I have no knowledge of the internals of zypper or yast, so I don’t know it it even feasible, but it would decrease the time needed to patch the system.

There is some good news for you: in cooperation with Marcus Hüwe the download on demand feature is now working seamlessly with cross-build, making it a combined “super feature”.

Also, I have put together a “condensed” cross-build in OBS document in the OBS Wiki Concepts collection.

New OBS cross-build installation packages will be provided inside openSUSE:Tools:Devel soon.

Have fun.

Handling references and bibliographic information is an essential part of all research. If you are writing just one article or just your diploma thesis maybe you don't need to use this kind of software because you will not have a lot of references. BUT, if you are writing A LOT of articles, reports, master/diploma/phd thesis then you definitevely will need a good software to manage your bibliographic database.

Here is how a bibliographic manager works. An author creates a document and cites his document with entries form a bibliographic database created earlier. After the author completed writing the paper he passes the document and the database through some application and the application incorporates all the references cited in the document from the database. This produces a final version of the document containing the text, graphics, etc. the author created along with the references he cited in a specific format.

I will not try here a comparison of free and non-free software available, just I would like to point some interesting links which I found when I started to use bibliographic management software. So here are the links:

• Reference management software from Wikipedia
• A comparison of management software
• Comparison of free bibliographic managers
• Finding the right bibliographic/reference tool
• Bibliography Management Software with a Detailed Analysis of Some Packages
• Evaluation of Reference Management Software (comparing Papyrus with ProCite, Reference Manager, Endnote, Citation, GetARef, Biblioscape, Library Master, Bibliographica, Scribe, Refs

I hope that the above links will be useful.

What do I prefer? I am using LaTeX for everything (presentations, posters, reports, letters, ... ) and BibTeX, so I need something which can use plain bibtex file. I am searching and download references from ISI Web of Knowledge. The naming convention for citation key (for the bib-keywords) which I am using (thanks to my supervisor for the suggestion) is the following:

• One author: First four letters AND last two digits of publication year (Prot08)
• Two authors: First two letters of both authors AND last two digits of publication year (TePr05)
• Three or four authors: First letter of each author AND last two digits of publication year (TRPS07)
• More than four authors: First four letters of first author AND last two digits of publication year
• If a key already exists: the next entries get a small letter behind the publication year, starting with b. (RoTe07b, RoTe07c)

I've been using KBibTex and KBib for a while now since I use linux. For me it's quite useful because it has a simple, no bloat GUI that does one thing - let's you add and maintain references. The minor point here is that they are available just for linux/bsd. Now, I played in the last weeks with Jabref (it is writen in Java and it can run on every platform: bsd/linux/mac/win). I still didn't find how to use it in order to search in ISI Web of Knowledge, but I thing I will change to it anyway, to have the same software on all platforms.

That's all and good luck in managing your bibliographic database.

I am using LaTeX (started with LaTeX 2.09, followed by LaTeX 3e) for everything technical and scientific (reports, articles, master/diploma thesis, presentations - yes, I am preparing my presentation with it, posters, letters, ..). In the last year I changed to pdfTeX in order to obtain directly pdf file output without intermediate steps like dvi and ps, and to replace eps files from my computer with pdf files. For Windows I am using MiKTeX with TeXnicCenter which is a great editor.

Of course that I need to include animations in my presentations (for example some simulations movies). I use all the time .avi files so here are just two methods to include them in pdf.

I saw that a lot of people included as well swf, mpeg, wmv, mpg, but in my case doesn't work with the second method, avi worked in both cases. Adobe Acrobat Reader (version 8.1.0) doesn't want to play this kind of movies (file unsuported). I couldn't include gif file. So, here are the methods:

• using "movie15" package:

    %include the package
    \usepackage{movie15}
    ....
    ....
    Click bellow to start the movie:\  
    % we can use also: mpeg wmv mpg swf
    \includemovie[poster]{5cm}{5cm}{movie.avi}

• using "multimedia" package:

    %include the packages
    \usepackage{multimedia}
    \usepackage{hyperref}
    ....
    ....
    Click bellow to start the movie:\  
    \movie[height=5cm,width=5cm,loop]{}{movie.avi}

If you know how to include gif in pdf files and to work in Acroread on Linux, then, please let me know.

Also this year I’ll attend the Linux day (a day dedicated to Gnu/Linux  and FLOSS that occurs every year in Italy) organized by my LUG. Guess what I’ll be talking about… ;)

While organizing the event somebody proposed to setup a local server with some music released under CC license. He suggested to download some albums from Jamendo (due to network issues we won’t be able to provide direct access to the website).

Since nobody wanted to download the albums by hand, last night I wrote a small ruby program that does the dirty job.

Requirements:

Ruby and json gem have to be installed on you machine.

Usage:

Help:[](http://www.flavio.castelli.name/wp- content/uploads/2008/10/jamendo_downloader.rb)

./jamendo_downloader.rb –help

Download the top 10 rock albums:

./jamendo_downloader.rb -g rock -t 10

Have fun

I think there’s nothing more to say… enjoy it!

{% gist 2437530 jamendo_downloader.rb %}

• Use a different color, like "Selected"?


• Only change the text color on hover?


• Both?

In my previous post I discussed how to call Gnuplot from C and Python language. If you are using Perl, then, here is the script:

    #!/usr/bin/perl
    # Generate postscript and png plot with GNUplot from Perl
    # Author: Ioan Vancea
    # Usage: Give "data file" as an argument for script

    use strict;
    use warnings;

    my $file = ARGV[0];

    # POSTSCRIPT
    open (GNUPLOT, "|gnuplot");
    print GNUPLOT <

If you are doing a lot of calculations/simulations, like me, using C or/and Python language, you also need to visualize your simulated data. One way to do it is just to generate/write a "data" file and plot it with your plotting preferred package after the simulation is finished. But maybe, sometimes, you want to see the graph in real time, so, here I would like to show a small C and Python program which calls Gnuplot and save the plot in png format.

C Example:

#include
/*
    Author: Ioan Vancea (www.vioan.eu)
    *****************************/
int main()
{
    FILE *pipe = popen("gnuplot -persist","w");
    fprintf(pipe, "set samples 40\n");
    fprintf(pipe, "set isosamples 40\n");
    fprintf(pipe, "set hidden3d\n");
    fprintf(pipe, "set xrange [-8.000:8.000]\n");
    fprintf(pipe, "set yrange [-8.000:8.000]\n");
    fprintf(pipe, "set zrange [-2.000:2.000]\n");
    fprintf(pipe, "set terminal png\n");
    fprintf(pipe, "set output 'graph.png'\n");
    fprintf(pipe, "set title 'We are plotting from C'\n");
    fprintf(pipe, "set xlabel 'Label X'\n");
    fprintf(pipe, "set ylabel 'Label Y'\n");
    /* fprintf(pipe, "plot 'datafile.dat' using 1:2\n");*/
    fprintf(pipe, "splot cos(x)+cos(y)\n");

  close(pipe);
  return 0;
}

The output:

Python Example (I use Gnuplot.py):

#!/usr/bin/env python

'''
    Author: Ioan Vancea (www.vioan.eu)
'''

import math
import Gnuplot
gp = Gnuplot.Gnuplot(persist=1)
x = range(1000)
y = [math.sin(a) + math.cos(a) + math.tan(a) for a in x]
data = Gnuplot.Data(x, y, title='Plotting from Python')
gp('set data style lines')
gp('set xlabel "Label x"')
gp('set ylabel "Label y"')
gp.plot(data);
gp.hardcopy(filename="pyplot.png",terminal="png")

The output:

I probably could make here the longest title just naming everything we have so far as designation for the job

So what is it about?

We want to have an official program to support local communities better. We already have some strong supporters which are doing an awesome job, now we need more of them. You might think of fedora ambassador or Ubuntu LoCo, but for a unique project like openSUSE we also should have a unique name. But of course it’s not all about the name, i posted yesterday a draft with more details and some open questions. We think that this program will help the project, and the people who are doing the job (without a name right now ), a lot.

Join the discussion at openSUSE-marketing!