Scumm Bar

OSGi DS Declarative Services example

noreply@blogger.com (Stefano Ghio) — Fri, 27 Jan 2012 17:08:00 +0000

In this post we will give a fair example of the workings of the OSGi DS services.

We are working with the Equinox OSGi framework, which is part of the Eclipse IDE (for Java). The code can be launched either inside Eclipse or from a standalone OSGi framework; for the latter option, grab the following jar packages from under the plugins/ folder of our Eclipse installation:


org.eclipse.osgi
org.eclipse.equinox.ds
org.eclipse.equinox.util
org.eclipse.osgi.services

and copy them in a folder of your choice.

Now open a command prompt, browse to that folder and type:

java -jar org.eclipse.osgi.jar -console

to make the OSGi prompt appear. From here you can issue a lot of commands to the OSGi framework, some of which are:

help
ss - shows the current status of the installed bundles
install file://path - installs the bundle available at the specified path. It will be given an unique numeric ID
uninstall ID
start ID
stop ID
refresh - forces a framework refresh and update of the bundles state

The bundles can be in only one of the following states at a time:

INSTALLED: the bundle has been successfully installed on the platform;

RESOLVED: all of the bundle's dependencies are currently available, the bundle is ready to be started or it has just been stopped;

STARTING: the bundle is starting, it is waiting for the method which takes care of the necessary start operations to return;

```
ACTIVE: the bundle is up and running;
```
STOPPING: the bundle is stopping, it is waiting for the method which takes care of the necessary stop operations to return.

There exists an additional state, UNINSTALLED, but it will never be shown by the framework.

In order for the DS component to work properly, you must install and start all the bundles copied before (org.eclipse.osgi excluded) inside the framework.

Now we can begin our example.

Suppose we have two services: HappyService and SadService, their interfaces: IHappy and ISad and a client: Customer who declares a dependency on the services by pointing to their interfaces using the DS method.

When a component declares it provides a service, the OSGi framework stores that information in its internal registry.

Download here the example's source code. Inside you will find:


Interface - IHappy.java

package it.eng.test.ds.happy;

public interface IHappy {
 public void imHappy();
}
Interface - ISad.java

package it.eng.test.ds.sad;

public interface ISad {
 public void imSad();
}
Implementation - HappyService.java

package it.eng.test.ds.happyservice;

import it.eng.test.ds.happy.IHappy;

public class HappyService implements IHappy{
 public void imHappy(){
  System.out.println("I'm happy :)");
 }
}
Implementation - SadService.java

package it.eng.test.ds.sadservice;

import it.eng.test.ds.sad.ISad;

public class SadService implements ISad{
 public void imSad(){
  System.out.println("I'm sad :(");
 }
}


If you inspect them, you will see that the two services offer a single, simple method which prints something on standard output.


Client - Consumer.java

package it.eng.test.ds.consumer;

import it.eng.test.ds.happy.IHappy;
import it.eng.test.ds.sad.ISad;

public class Consumer {
 private IHappy happy;
 private ISad sad;
 
 public synchronized void bindHappy(IHappy happy){
  this.happy = happy;
  happy.imHappy();
 }
 
 public synchronized void unbindHappy(IHappy happy){
  this.happy = null;
  sad.imSad();
 }
 
 public synchronized void bindSad(ISad sad){
  this.sad = sad;
  sad.imSad();
 }
 
 public synchronized void unbindSad(ISad sad){
  this.sad = null;
  happy.imHappy();
 }
 
 public void activate(){
  System.out.println("I'm here");
 }
 
}

The consumer declares the dependency on the two services by requiring their interfaces and has some methods of his own:


activate: this method is called as soon as the client bundle is started;
bind*: this method is called immediately after the required *Service becomes available on the framework;
unbind*: this method is called immediately after the required *Service becomes unavailable on the framework.

The framework knows that Consumer needs those particular services since he declared it in his XML configuration which must be put under the OSGI-INF/ folder:

<?xml version="1.0" encoding="UTF-8"?>
<scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.1.0" name="it.eng.test.ds.consumer">
   <implementation class="it.eng.test.ds.consumer.Consumer"/>
   <reference bind="bindHappy" cardinality="0..1" interface="it.eng.test.ds.happy.IHappy" name="IHappy" policy="dynamic" unbind="unbindHappy"/>
   <reference bind="bindSad" cardinality="0..1" interface="it.eng.test.ds.sad.ISad" name="ISad" policy="dynamic" unbind="unbindSad"/>
</scr:component>

In there the bundle is saying that the class it.eng.test.ds.consumer.Consumer dynamically and optionally depends on one of the possible it.eng.test.ds.happy.IHappy interface implementations and that when one of them becomes available or unavailable inside the framework, its bindHappy or unbindHappy method should be called.

The dynamically policy attribute means that the bundle is able to work properly even when the services are dynamically switched; the alternative would be static, which would require the DS to deactivate the component and create a new instance each time the required service changes.

The dependency is optional since the cardinality was set to 0..1, meaning the component can be started even if that particular dependency is not currently available, contrarily to 1..1 which means instead that it is mandatory. Another alternative would be 0..N, which would require the DS to invoke the associated method multiple times, one for each service instance currently available in the registry.

Furthermore, the name of the bind* and unbind* methods can be changed as pleased as long as it reflects the ones written in the java code.

On their side, the two services must declare their own XML configurations, listing the interface implementations offered and the classes implementing them:

HappyService XML:

<?xml version="1.0" encoding="UTF-8"?>
<scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.1.0" name="it.eng.test.ds.happyservice">
   <implementation class="it.eng.test.ds.happyservice.HappyService"/>
   <service>
      <provide interface="it.eng.test.ds.happy.IHappy"/>
   </service>
</scr:component>

SadService XML:

<?xml version="1.0" encoding="UTF-8"?>
<scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.1.0" name="it.eng.test.ds.sadservice">
   <implementation class="it.eng.test.ds.sadservice.SadService"/>
   <service>
      <provide interface="it.eng.test.ds.sad.ISad"/>
   </service>
</scr:component>

When we install all those bundles inside the same OSGi framework and start them, we see that Consumer prints on the standard output the string "I'm here" right after it is starts and then, alternatively depending on their service implementation bundle's state, the strings: "I'm happy :)" and "I'm sad :(".

Why beer is good for the brain

noreply@blogger.com (Stefano Ghio) — Sun, 15 Jan 2012 10:04:00 +0000

Well ya see, Norm, it's like this. A herd of buffalo can only move as fast as the slowest buffalo. And when the herd is hunted, it is the slowest and weakest ones at the back that are killed first.
This natural selection is good for the herd as a whole, because the general speed and health of the whole group keeps improving by the regular killing of the weakest members.

In much the same way, the human brain can only operate as fast as the slowest brain cells. Excessive intake of alcohol, as we know, kills brain cells. But naturally, it attacks the slowest and weakest brain cells first. In this way, regular consumption of beer eliminates the weaker brain cells, making the brain a faster and more efficient machine.
That's why you always feel smarter after a few beers.

Cheers, 1982

ITALIANO:

Beh vedi, Norm, funziona cosi'. Una mandria di bufali puo' muoversi al piu' velocemente come il bufalo piu' lento. E quando la mandria viene cacciata, sono i piu' lenti e deboli rimasti indietro ad essere uccisi per primi.

Questa selezione naturale giova alla mandria stessa, perche' la salute e la velocita' generale di tutto il gruppo continua a migliorare grazie all'eliminazione costante dei membri piu' deboli.

Quasi allo stesso modo, il cervello umano puo' operare al piu' velocemente come le piu' lente cellule cerebrali. Un'assunzione eccessiva di alcool, come sappiamo, uccide le cellule cerebrali. Ma naturalmente, attacca le piu' lente e deboli per prime. In questo modo, un'assunzione regolare di birra elimina le cellule cerebrali piu' deboli, rendendo il cervello una macchina piu' rapida ed efficiente.

Ecco perche' ti senti sempre piu' furbo dopo un paio di birre.

[Sheet music] Take me home, country roads piano

noreply@blogger.com (Stefano Ghio) — Tue, 08 Nov 2011 17:46:00 +0000

This version is the one from the movie Whispers of the heart and it's based on the John Denver's original one.

Questa versione e' del film Whispers of the heart ed e' basata sull'originale di John Denver.

Scarica lo spartito/Download sheet music.

[Sheet music] Starcraft Terran theme piano

noreply@blogger.com (Stefano Ghio) — Tue, 08 Nov 2011 17:42:00 +0000

Scarica lo spartito/Download sheet music.

[Sheet music] Murder, she wrote piano theme - La signora in giallo

noreply@blogger.com (Stefano Ghio) — Tue, 08 Nov 2011 17:41:00 +0000

Scarica lo spartito/Download sheet music.

How to contact Facebook or delete your account

noreply@blogger.com (Stefano Ghio) — Tue, 27 Sep 2011 18:34:00 +0000

Contacting Facebook can really be a pain, but definitely deleting your account is even harder. Since they rely on your data to survive, they will hang on to it as long as possible.

Luckily, Mary Smith gathered all possible ways to contact Facebook and receive support. Feature requests, suggestions, bug reports and account deletion can all be found there.

You can even request Facebook to send you a CD copy of all the data they have about you accordingly with your country's privacy laws.

By the way, good luck at getting Facebook to reply to you, especially with the data request. If they don't answer, insist since they MUST satisfy your request within a limited time.

Legend of Dragoon fix disc 2 freeze after Lenus & Regole battle

noreply@blogger.com (Stefano Ghio) — Tue, 13 Sep 2011 14:34:00 +0000

ENGLISH: please refer to supercheats, quick summary: beat the battle without ever going Dragoon

ITALIANO:

The Legend of Dragoon é uno di quei giochi che non risentono dell’etá. Purtroppo, se si prova a giocarlo su una qualsiasi console che non sia la ormai rara PlayStation 1 (PS2, PS3, PSP o usando l’emulatore PSX), per qualche motivo dopo la battaglia contro Lenus e Regole verso la fine del disco 2, lo schermo diventa nero ed il gioco va in freeze senza possibilitá di recupero.

Fortunatamente (grazie Google search e supercheats!), esiste una soluzione: terminare la battaglia senza mai trasformare alcun personaggio in Dragone. La cosa non é poi cosí impossibile come sembra, basta seguire alcuni accorgimenti:

avere il party ad un livello di almeno 20
inserire Meru nel party poiché, essendo dello stesso elemento (acqua) dei due boss, riceve meno danni dai loro attacchi e gli oggetti magici d’attacco usati da lei sono piú efficaci
inserire Shana nel party poiché gli oggetti magici d’attacco usati da lei sono piú efficaci
fare grande scorta di oggetti d’attacco come Incenerimento (bersaglio singolo) e Magma sgorgante (bersagli multipli), molto efficaci specie se utilizzati da Dart, Meru o Shana
puó aiutare equipaggiare Dart con la Lama Rovente perché aggiunge attacco fuoco a cui sono deboli i due boss
evitare di inserire Kongol o Albert nel party per via della loro scarsa difesa magica e lentezza
in alternativa a Shana, inserire Rose o Haschel nel party con il compito di utilizzare oggetti di recupero ed attaccare fisicamente Lenus verso la fine della battaglia quando non si hanno piú oggetti d’attacco
puó aiutare equipaggiare con l’Anello del Bandito il membro piú lento del party, equipaggiare con l’Anello Lenitivo il membro del party che sará addetto alla cura e con l’Anello Fisico il membro del party con meno PF

Portugal.. como un Jarro

noreply@blogger.com (Stefano Ghio) — Wed, 10 Aug 2011 06:20:00 +0000

Ci sono un Irlandese, un Portoghese e due Italiani in Portogallo con un jarro in mano.. Scopri come va a finire guardando le foto

Ps: If anyone knows who's the girl in the background, please say it in a comment!

GNOME 3 add applications taskbar/panel

noreply@blogger.com (Stefano Ghio) — Sun, 31 Jul 2011 21:41:00 +0000

GNOME 3 does not have, like GNOME 2, two taskbars: one for the applications and one for the system tray. It is possible to add the application taskbar (which includes a system tray panel too) manually with the project tint2. All instructions for installing under different distros are available directly on the developers website.

ITALIANO:

GNOME 3 non ha, a differenza di GNOME 2, due taskbar: una per le applicazioni e una per la system tray. É possibile aggiungere la barra delle applicazioni (che include anche un pannello di tray) manualmente tramite il progetto tint2. Tutte le istruzioni per l’installazione sotto differenti distribuzioni sono disponibili direttamente sul sito degli sviluppatori.

GNOME 3 enable right click on desktop and show icons

noreply@blogger.com (Stefano Ghio) — Sun, 31 Jul 2011 21:32:00 +0000

GNOME 3 by default doen’t show any icon on the desktop and does not allow right-clicking it. You could change this behaviour manually:

run yum install dconf-editor as root or install it via add/remove software and launch it when it’s ready
navigate the menus through org –> GNOME –> Desktop –> Background
search for the show-desktop-icons entry and chek its checkbox

ITALIANO:

GNOME 3 di base non mostra alcuna icona sul desktop e non permette il click destro. Si puo’ modificare questo comportamento manualmente:

lanciate yum install dconf-editor da root o installatelo via add/remove software ed avviatelo al termine
navigate i menu attraverso org –> GNOME –> Desktop –> Background
cercate la voce show-desktop-icons e selezionate la checkbox associata

GNOME 3 add minimize and restore buttons to windows

noreply@blogger.com (Stefano Ghio) — Sun, 31 Jul 2011 21:24:00 +0000

GNOME 3 by default shows only the “close” button on windows. You could add the other two (minimize and restore/maximize) manually:

run yum install gconf-editor as root or install it via add/remove software and launch it when it’s ready
navigate the menus through Desktop –> GNOME –> Shell –> Windows
search for the button_layout entry and edit its value to :minimize,maximize,close (colon included!)
restart nautilus or log out and in again to see the changes take effect

ITALIANO:

GNOME 3 di base mostra solo il bottone “chiudi” sulle finestre. Si possono aggiungere gli altri due (minimizza e ripristina) manualmente:

lanciate yum install gconf-editor da root o installatelo via add/remove software ed avviatelo al termine
navigate i menu attraverso Desktop –> GNOME –> Shell –> Windows
cercate la voce button_layout e modificate il suo valore a :minimize,maximize,close (due punti inclusi!)
riavviate nautilus o fate log out e log in di nuovo per vedere il cambiamento in azione

Realtek wireless on Fedora

noreply@blogger.com (Stefano Ghio) — Sun, 31 Jul 2011 21:05:00 +0000

This article applies to the 819x Realtek wireless cards series like models 8191SEvB, 8191SEvA2, 8192SE, …

Main reference site is Stanislaw Gruszka’s compact wireless website.

You can either try the -stable version or the –next. Both have different kernel requirements, the –next version, though more unstable, is compiled against the latest kernel version so you should run yum update kernel as root before installing the appropriate package for your system.

After installation you will have to reboot the system before being able to use and control your wireless card through NetworkManager.

ITALIANO:

Questo articolo si applica ai modelli di schede wireless Realtek serie 819x quali 8191SEvB, 8191SEvA2, 8192SE, …

Il sito di riferimento é compact wireless di Stanislaw Gruszka.

Potete provare sia la versione -stable che la –next. Entrambe hanno differenti requisiti di kernel, la versione –next, sebbene piú instabile, é compilata per l’ultima versione del kernel supportata dal sistema per cui é sufficiente lanciare yum update kernel da root prima di installare il pacchetto corretto per il proprio sistema.

Al termine dell’installazione sará necessario riavviare il sistema prima di poter usare e controllare la propria scheda wireless attraverso il NetworkManager.

[MatLab] EM – Expectation Maximization reconstruction technique implementation

noreply@blogger.com (Stefano Ghio) — Wed, 20 Jul 2011 16:33:00 +0000

EM – Expectation Maximization is an iterative algorithm used in tomographic images (as in CT) reconstruction, very useful when the FBP – Filtered Back Projection technique is not applicable.

Basic formula is:

f_k+1 = (f_k / alpha) (At (g / (A f_k)))

where:

f_k is solution (the resulting reconstructed image) at k-th iteration, at first iteration it is our guess
g is image sinogram (what we get from the scanning)
A f_k is Radon transform of f_k
At is inverse Radon
alpha is inverse Radon of a sinogram with all values 1 which represents our scanning machine

Get the source code here.

[MatLab] SIRT - Simultaneous Iterative Reconstruction Technique implementation

noreply@blogger.com (Stefano Ghio) — Wed, 20 Jul 2011 16:26:00 +0000

SIRT – Simultaneous (algebraic) Reconstruction Technique is an iterative algorithm used in tomographic images (as in CT) reconstruction, very useful when the FBP – Filtered Back Projection technique is not applicable.

Basic formula is:

f_(k+1) = f_k + At (g - A f_K)

where:

f_k is solution (the resulting reconstructed image) at k-th iteration, at first iteration it is our guess
g is image sinogram (what we get from the scanning)
A f_k is Radon transform of f_k
At is inverse Radon

Get the source code here.

[MatLab] Filter a tomographic image in Fourier’s space

noreply@blogger.com (Stefano Ghio) — Wed, 20 Jul 2011 16:16:00 +0000

MatLab has built-in functions to simulate acquisition and elaboration of tomographic (as in CT) images. When it comes to filtering the image prior to back-projecting it, it is possible to do it yourself without relying on the (good as in Shepp-Logan) filters MatLab has.

We will filter our image in Fourier’s space. For each column of the sinogram, we:

apply the Fourier transform
filter it
apply the Fourier antitransform

When we reconstruct our image WITHOUT having MatLab apply any filter, we’ll see the image, filtered with our filter, as a result. Get the source code here.

[PHP] PageRank implementation

noreply@blogger.com (Stefano Ghio) — Wed, 06 Jul 2011 14:21:00 +0000

There are two possible PageRank implementations: the power method and the iterative method. We will describe both.

To check the results obtained we provide a scri'pt to generate a .gexf file to be opened with Gephi.

Test datasets are available at the Toronto university website.

Technologies used:

PHP
Gephi
XML

1.Power method

This method takes longer than the other one, however the result is equally right. Using a sparse matrix instead of the full one may help speed up the process.

Method description:

Pick the NxN input matrix and make it stochastic, call it A
Create the P" matrix as alpha*A+(1-alpha)*M with alpha a factor which describes the probability of a random jump and M an NxN matrix filled with values 1/N
Create starting vector v_0 with length N filled with values 1/N
Compute v_m = v_m-1*P" where the first time v_m-1 is exactly v_0
Compute the difference v_m - v_m-1 which should converge to 0
When the difference doesn't vary over a certain threshold or i iterations have been made, stop. v_m should contain the PageRank for every page

To run the program you must have the nodes and adj_matrix files from the chosen dataset. The implementation source code is found here here.

NOTE: Due to Apache and PHP limitations, you may have to modify the php.ini file to grant more memory to the scripts (if you don't want to store the matrix on filesystem like we did) by setting the memory_limit parameter to at least 768MB and raising the maximum script execution time to 5 minutes(300 seconds) with max_execution_time.

2. Iterative method - found on phpir

To use this method you must have the nodes and adj_list files from the chosen dataset.

Method description:

Each page is given a starting PR of 1/N where N is the number of nodes in the graph. Each page then gives to every page it links a PR of current_page_PR/number_of_outbound_links.
It's introduced a dampening factor alpha (0,15) which represents the probability of making a random jump while visiting the graph or when reaching a cul de sac.

PR_new = alpha/n + (1-alpha)*PR_old

Every PR is then normalized between 0 and 1.

The process keeps going until it has reached i iterations or the difference between old and new PR doesn't vary over a certain threshold.

Our implementation is available here.

3. Gephi parser:

To use the parser you you must have the nodes and adj_list files from the chosen dataset. The parser outputs a .gexf file to be opened with Gephi. Here is a sample .gexf file obtained by parsing the first dataset available on the site (the one about abortion).

pro-AD website: MRI analysis for prodromal Alzheimer’s assessment

noreply@blogger.com (Stefano Ghio) — Wed, 25 May 2011 13:39:00 +0000

Recently I participated in the pro-AD’s website development.

pro-AD is a website created at DIFI, the University of Genoa’s Department of Physics, to help medics automagically analyse MRI images for the prodromal Alzheimer's disease assessment.

Registered medics can easily submit DICOM or NII files through the website to their private local folder via the java applet JUploader or the PHP uploader which is shown automatically when no java plugin is detected on the user's browser. They can then modify the information associated with those images: age, gender and an optional unique ID - no personal data about the patients is stored anywhere anytime during the process.

Easy access for the medic's personal profile is provided through a dedicated page; if a valid e-mail address is provided, it is possible to enable e-mail notifications about processing results.

When one or more files are selected for processing, the server enqueues them in a multithreaded pipeline and starts the analysis. At the end, a single number which describes the patient's likelihood of being affected in the near future by the disease is returned for each file sent to processing. If the file processed was of really bad quality or was not a valid file, the process fails and an error is shown instead of the result.

All results are stored for easy future access and can be viewed and exported in XLS format from a dedicated page. If a file is sent to processing more times, only the latest result is stored.

[PHP] Create XLS document

noreply@blogger.com (Stefano Ghio) — Wed, 25 May 2011 13:18:00 +0000

If you need to create XLS documents via PHP, you may need these functions:

//XLS Begin of file
function xlsBOF() {
echo pack("ssssss", 0x809, 0x8, 0x0, 0x10, 0x0, 0x0);
return;
}
//XLS End of file
function xlsEOF() {
echo pack("ss", 0x0A, 0x00);
return;
}
//Writes a number in a cell
function xlsWriteNumber($Row, $Col, $Value) {
if($Value == null){
xlsWriteLabel($Row, $Col, $Value);
}
else{
echo pack("sssss", 0x203, 14, $Row, $Col, 0x0);
echo pack("d", $Value);
}
return;
}
//Writes a string in a cell
function xlsWriteLabel($Row, $Col, $Value ) {
$L = strlen($Value);
echo pack("ssssss", 0x204, 8 + $L, $Row, $Col, 0x0, $L);
echo $Value;
return;
}

//Creates headers to download the file
function xlsWriteHeader(){
// Send Header
header("Pragma: public");
header("Expires: 0");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Content-Type: application/force-download");
header("Content-Type: application/octet-stream");
header("Content-Type: application/download");;
header("Content-Disposition: attachment;filename=EXPORTNAME.xls ");
header("Content-Transfer-Encoding: binary ");
}

[PHP] Send mail with attachment using PEAR

noreply@blogger.com (Stefano Ghio) — Wed, 25 May 2011 13:08:00 +0000

If you use PEAR and want to send mails with attachments via PHP, you may find this helpful.

First, ensure you have installed PEAR’s Mail and Mail_mime packages. Then, you just need a function like this:

function send_mail($mail, $subject, $bodytxt, $bodyhtml, $attachment){
    require_once('Mail.php');
    require_once('Mail/mime.php');
    //mail parameters, this is the basic one
    $params = array("host"=>"YOUR_HOST");
    //creates smtp mail object
    $mail_sender = Mail::factory("smtp", $params);
    //creates mail headers
    $headers = array("From"=>"YOUR_ADDRESS", "To"=>$mail, "Subject"=>$subject);
    //creates attachment and body fields
    $crlf = "\n";
    $mime = new Mail_mime($crlf);
    $mime->setTXTBody($bodytxt);
    $mime->setHTMLBody($bodyhtml);
    $mime->addAttachment($attachment, "ATTACHMENT_TYPE");
    //never change these lines order
    $body = $mime->get();
    $headers = $mime->headers($headers);
    $error=$mail_sender->send($mail, $headers, $body);
    return $error;
}

where:

YOUR_HOST is your mail host, something like smtp.gmail.com
$mail is the recipient’s mail address
$bodytxt is the mail’s body in TXT format, do not use HTML markup here!
ATTACHMENT_TYPE is the attachment’s MIME type as per IANA’s specifications, something like image/jpeg
if you change the order of the last lines, the attach operation will not work

[PHP, XML] Twitter friends graph

noreply@blogger.com (Stefano Ghio) — Fri, 13 May 2011 16:44:00 +0000

Brief example on how to create and draw some Twitter user’s friends graph.

Piccolo esempio di come creare e disegnare il grafo dei friends di un dato utente Twitter.

English:

With friends Twitter means “people whom the user follows”. Starting from a chosen user, we grab all his friends until a depth level of 3 and we create a XML file with a proper structure to be opened by Gephi in order to graphically visualize the result. The number of users we get is far lower than the real one due to Twitter API’s limitations.

To create the gexf file for Gephi, just run the HowDoYouGraph script after editing the $username variable with the desired username. After a little coffee break, in the same folder as the script you should find a file named grafo.gexf.

Show an example graph for user VivoMikiX and download the gexf source.

Stats about the undirected example graph:

Total nodes: 5013
Total edges: 5539
Medium degree = 2.21
Diameter = 6
Density = 0
Modularity = 0.876
- Number of communities = 72
Weakly connected components = 1
Medium clustering coefficient = 0.014
- Total triangles = 202
Eigenvector centrality with 300 iterations = 0.0325
Medium path length = 4.496
- Number of shortest paths = 25125156
- Radius = 3

Italiano:

Con friends si intendono tutte le persone che l'utente segue. Partendo da un dato utente, recuperiamo i suoi friends fino al livello 3 e generiamo un file XML con una struttura gradita a Gephi per visualizzare graficamente il risultato. Il numero di utenti recuperati e' inferiore al numero reale a causa di limitazioni imposte dalle API di Twitter.

Per creare il file gexf per Gephi, basta far girare lo script HowDoYouGraph dopo aver modificato la variabile $username con lo username desiderato. Dopo aver preso un caffe', nella stessa cartella dello script apparira' un file chiamato grafo.gexf che e' quello che ci interessa.

Visiona un grafo di esempio per l’utente VivoMikiX e scarica il file gexf sorgente.

Statistiche sul grafo d’esempio, considerandolo indiretto:

Totale nodi: 5013
Totale archi: 5539
Grado Medio = 2.21
Diametro = 6
Densità = 0
Modularità = 0.876
- Numero di Comunità = 72
Componenti connesse debolmente = 1
Coefficiente di Clustering Medio = 0.014
- Triangoli totali = 202
Centralità di autovettori con 300 iterazioni = 0.0325
Lunghezza cammino medio = 4.496
- Numero di percorsi piu' corti = 25125156
- Raggio = 3

Paris.. like a boss

noreply@blogger.com (Stefano Ghio) — Mon, 25 Apr 2011 21:11:00 +0000

Cosa ottieni se prendi tre fieri e li metti a Parigi? Scoprilo guardando le foto!

[PHP, JavaScript] Twitter, Google Maps, YouTube API mashup

noreply@blogger.com (Stefano Ghio) — Thu, 31 Mar 2011 11:48:00 +0000

Where you followin' me?

English:

A mashup with Twitter, Google Maps and YouTube APIs.

We grab some Twitter user's followers, show them on Google Maps and include YouTube videos about the city where most followers live.

Italiano:

Un mashup con le API di Twitter, Google Maps e YouTube.

Si recuperano i follower di un certo utente Twitter, si mostra la loro concentrazione su Google Maps e si includono dei video riguardanti la cittá in cui risiede la maggior parte dei follower.

Scarica la documentazione/Download the project docs.

Scarica i file del progetto/Download the project files.

[Java] Calcolatrice v 1.1

noreply@blogger.com (Stefano Ghio) — Sun, 28 Nov 2010 12:52:00 +0000

Sì tutti la aspettavano e finalmente è uscita! La mitica, insuperabile, potentissima, e graficamente accattivante Calcolatrice v 1.1 è qui!

Qui scarica il .jar (doppio click per farlo partire). Serve un ambiente java installato, se non lo hai scaricalo da qui.

Qui scarica i sorgenti java.

Prodotto rilasciato sotto licenza di uccidere, GPLv2, CreativeCommons.

[C] Stable Matching v2.5.3

noreply@blogger.com (Stefano Ghio) — Sun, 28 Nov 2010 12:51:00 +0000

Finalmente completato e ampiamente testato, è ancora fresco di compilazione. "Stable Matching v2.5.3" cambierà il vostro modo di cercare un/a compagno/a. Potente, intuitivo, annienta-noob-inabili-all'utilizzo-correggendo-ogni-loro-errore-di-inuput-e-costringendoli-a-crasharmelo-soltanto-con-una-kill, non manca di nulla, a parte un'interfaccia.

Qui i sorgenti:

libreria

funzioni

main

Qui il documento di progetto.

Il programma è in inglese, i commenti al codice ed il documento di progetto sono in italiano, tanto il C è universale. Compilare con gcc o quello che volete. Funziona da riga di comando. Rilasciato sotto GPLv2 e CreativeCommons.

[Java] Pda Maps v1.0

noreply@blogger.com (Stefano Ghio) — Sun, 28 Nov 2010 12:50:00 +0000

Più potente del TomTom, più stiloso dell'iPhone, più completo del tuttocittà.. ecco a voi Pda Maps v1.0!

Nello zip c'è tutto, incluso documento di progetto e readme.

Per compilare: javac Pda.java

Per far partire: java Pda

Questa volta niente .jar per comodità. Sono allegati due file mappa, altri aggiuntivi vanno creati a mano.