Making up after the 100-Day Plan

After more than four months of intense activity, and after the end of the 100-Day Plan it’s time to sum up what was achieved since the release of the 0.7 version. Most of the objectives have been carried out and Gephi has been downloaded more than 17K times since February. The future looks bright and more and more people are interested using and developing the software. Networks are gaining a lot of momentum in the research community and in the industry, by being a generic and extensible platform we position Gephi as a reference tool. If you’re interested funding us, please let us know.

To beta version

Four versions have been released and a lot of bugs have been fixed during this period. The current version is 0.7 alpha 4, released last month. New features were also developed, with the help of the developer community and were quickly deployed, for instance PDF Export and new Metrics. Not later than yesterday, new bug-fixes were deployed and available through Gephi updates.

The milestone date is also fixed for the 0.7 beta: August 14, 2010. The aim is to fix remaining bugs until this date. If you notice one, please consider reporting it.


A Quick Start Guide and a Visualization Tutorial have been written. The community made great tutorials also, which made a huge difference. Kudos to them. The forum has also showed great ability to connect with users and provide quick support. Many efforts are still needed in that way and hope to get more support writing tutorials.


We completed the Gephi Manifesto, to understand the project’s goals and aims.


The video Introducing Gephi 0.7 had a huge success, viewed more than 12K times. It was done to promote the release of the 0.7 version and succeeded in this job. Gephi has now its place among graph visualization software and is already recognized for its easiness and efficiency. But above all, the audience see great potential in Gephi and many people are thinking how they could use or reuse Gephi for achieving bigger tasks. That is very positive and we are cheering developers to code plug-ins.

Follow the #madewithgephi hashtag on Twitter to see recent comments. The Gephi team also attended the IEEE EuroVis conference in June and will provide software demonstration at Sunbelt XXX next week, on Friday July 2.


Thought the 0.7 beta is still in preparation, the new developments still continue and are now in a very active period. Indeed, six Google Summer of Code students are working hard and are preparing outstanding improvements. The whole code is also profiting from the toolkit project, where essential modules are built together in a single JAR in order to be reused as a Java library. Good progress is made on this project. It is very important for many developers who wants to reuse Gephi features in other Java applications. So stay tuned about GSoC updates and gephi-toolkit!

The roadmap and blueprints page also got a lifting.

We would like also to reinforce interoperability with other tools and develop connectors to new file formats.

Developers tutorials

New help pages for developers were created: Checkout Code, Configuring NetBeans and Plugin Quick Start. HowTo for extending Gephi features have been written also, including layout, metric and import and were already used by third-parties developers to create new plugins.

The next tutorial will concentrate on the gephi-toolkit project and how to reuse Gephi as a Java library.

Many other tasks are on the way, notably translating Gephi in French and Spanish and preparing Gephi Student Program. We are very interested involving CS students and propose to them challenging tasks for a semester or a quartile. We hope to interest professors about that.

One more thing, after discussing with the community members we decided to move to AGPL licence for the beta version. The GNU Affero General Public License is a modified version of the ordinary GNU GPL version 3. It has one added requirement: if you run the program on a server and let other users communicate with it there, your server must also allow them to download the source code corresponding to the program that it’s running. If what’s running there is your modified version of the program, the server’s users must get the source code as you modified it. It is specifically designed to protect the Gephi Toolkit.

Gephi Quick Start Tutorial

Check out the first Gephi tutorial, which introduce the basic steps to network visualization in Gephi.

pdf Tutorial: Download it in PDF.

The tutorial follows the following steps with LesMiserables sample dataset. You can find other network datasets on the wiki.

  • Import file
  • Visualization
  • Layout
  • Ranking (color)
  • Metrics
  • Ranking (size)
  • Layout again
  • Show labels
  • Community-detection
  • Partition
  • Filter
  • Preview
  • Export
  • Save

Something is missing? Please continue the discussion about this tutorial on the forum. Feedback and criticism are welcomed.

GSoC 2009 student interview

Today I am pleased to interview Helder Suzuki, Gephi student at Google Summer of Code 2009.

Helder is a Computer Engineer student at Instituto Tecnológico de Aeronáutica and participated as a student in the 2009 Google Summer of Code. He’s currently working as a Software Engineer Intern at Google in Mountain View, California.


Sebastien Heymann: Hi Helder Suzuki, you took part in Gephi with the Google Summer of Code 2009 (GSoC), by handling the layout module and implementing the Yifan Hu’s multi-level algorithm. Could you explain why you chose this project, in particular why getting involved in Gephi although there are such great other organizations like Debian, WordPress or Mozilla?
Helder Suzuki: I really believe in the power of graphs application in variety of problems, this is a very hot topic and it’s gaining a lot of momentum in the research community and in the industry. My previous research was related to graphs, so I had some experience in the area already, it made a lot of sense for me to apply for Gephi.

Continue reading →

Gephi’s 100-Day Plan

Gephi team is very proud to announce 0.7 version of the software, after almost one year of hard, yet passionate work. You can download and try the alpha version with various datasets. Please give us all feedback on our new forum.

Gephi is turning now in a fully collaborative free software project, as its software architecture allows collaborative development. The 0.7 project was a complete rewriting of the code in a modular way. Features were spitted in modules that can be developed and managed by different developers more easily. The Google Summer of Code 09 was a perfect way to experience our architecture. The modules developed at that time are now fully integrated in the 0.7alpha release. We plan to have many developers interested by creating plugins for Gephi. We oriented our new website in that way, have a look on the Plugin Center. Plugins could be anything, from a new layout algorithm to the connector that build graphs from your enterprise data. If you’re interested, please join the discussion on the forum.

We hope to collaborate with the entire community to help drive network visualization forward. Gephi’s aim is not only proposing unseen features, but above all build a professional tool that works and serve community’s needs.

Official 100-Day plan, presented as top priorities first

  • Fix all reported bugs and improve usability. The 0.7 beta version will be released.
  • Fill users’ Quick Start guide and create a simple tutorial how to use Gephi.
  • Documentation, documentation and more documentation.
  • Make a feature-madness video, to let people know us.
  • Create tutorial pages for plugin development. At least layout, metrics and import.
  • Fill the Plugin Portal documentation on the wiki.
  • Create a Manifest and fill “Goals and Aims” on the website. Share our passion for graph visualization and highlight most challenging tasks.
  • Start Gephi Student Program, by proposing a set of programming tasks that can be managed in a semester or a quartile by computer science students.
  • Post blog articles about our approach and how Gephi is different (and great!).
  • Reorganize 0.7 specifications and build a clear roadmap and a discussion space for future developments. Invite people to join the specification team.
  • Finish documenting Gephi’s API.
  • Give more insight which dataset Gephi can deal with, get closer from users’ needs by learning which networks they wants to visualize and support them in this task.

Please consider joining us for achieving these tasks! See the wiki.

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Gephi initiator interview: how “Semiotics matter”

Today I have the honnor to interview a special member of Gephi Team: Mathieu Jacomy.

Mathieu is an engineer, a founder of the WebAtlas NGO, teacher in Sciences Po Paris, and leads R&D in the TIC Migrations program in the Fondation Maison des Sciences de l’Homme and Telecom ParisTech school.
He is the main developer of the “Navicrawler” software. He also created the first Gephi prototype.


Sebastien Heymann: Hi Mathieu Jacomy, you are the creator of Graphiltre, the first Gephi prototype that you developed in 2006. What was the purpose of making a yet-another-graph-software?
Mathieu Jacomy: Hi ! I’m glad to answer your questions, and I hope our readers will be pleased to know more about Gephi.

At this time I was analyzing a lot of graphs and I wasn’t satisfied by the existing free tools. That’s why I started to build my own tools.

I had no money to use professional tools, and I needed to understand precisely what the software was doing : the open source, free softwares perfectly fit these constrains.
I was using the amazing software Guess proposed by Eytan Adar, that himself built for his own needs. I was doing quite the same thing as him, and I couldn’t start to explore graphs without this tool.
But I wasn’t satisfied because the software didn’t allow so much manipulations. I couldn’t look at the substructures as easily as I wanted, and it was difficult to make nice cartographies.
I was dreaming of a “graph-dedicated Photoshop“, a visualization-oriented software rather than a script-oriented tool.

A good way to figure out what I mean is to look at the spatialization process. In famous softwares such as Pajek or Guess, you have algorithms called “layout”, “force-vectors” or “energy model”. These algorithms give its shape to the graph, and it is probably the most critical part of the process to build a clear visualization. Because the substructures or “patterns” that one may see in the image strongly depend on the algorithm and the settings chosen. But in the same time, most of users also want to quickly look at the global shape of the graph, and may not be aware that it’s important to search for the best algorithm to use depending on the time you have, the quality you want, the size of the graph, its degree distribution, the substructure that you expect to recognize… I was careful with these algorithms but even if I understood their principles and specificities, I couldn’t figure out how they were transforming the graph, and I couldn’t evaluate their differences.

Why? Because in these softwares you can’t :
– Manipulate the graph while the algorithm is running
– Modify the settings while the algorithm is running
– And sometimes, you can’t event see the graph while the algorithm is running
How can you just understand what’s happening there? Of course I started to work on a software that allowed this. But the same kind of problems appears again in other parts of the process, like filtering, image exporting… Pajek is clearly built in a mathematical perspective. Guess is more user-friendly, but not enough. I didn’t want a tool for mathematics experts, but a tool for people that actually have to explore and understand graphs. A professional tool for a job that didn’t exist at this time.

This was the starting point of “Graphiltre“. Building a graph exploration system so that you can understand what you are doing by looking at what happens on the screen, and do anything (including filtering) without typing a single script line.

Continue reading →

CPAN-Explorer, an interactive exploration of the Perl ecosystem

We are proud to announce the first Gephi-based system for exploring a complex network, CPAN-Explorer. This is a visualization project aiming at analyzing the relationships between the developers and the packages of the Perl language, known to be organized as the CPAN community (Comprehensive Perl Archive Network). Produced by RTGI Labs and our team, it was initially discussed in a talk at the FPW’09.

You can download original graph source files from each subproject page.
Available formats are: GEXF (Gephi graph format), GDF (Guess graph format), SVG, and PDF.
For some of the subprojects, an embedded javascript visualization is also available. For the community graph, a special Flash webpage is available for online exploration.


map of the Perl community on the Web

We generated two maps (authors and modules) using the CPANTS data. For the websites, we crawled a seed generated from the CPAN pages of the previous authors. Each of this graphs are generated using a force base algorithm.

All the map are available in PDF files, in creative common licence. The slides are in french, but we will explain the three maps here.

Flash interface

CPAN’s modules

The first map is about the modules available on the CPAN. We selected a list of modules which are listed as dependancies by at least 10 others modules, and the modules who used them. This graph is composed of 7193 nodes (or modules) and 17510 edges. Some clusters are interesting:

  • LWP and URI are really the center of the CPAN
  • a lot of web modules (XML::*, TemplateToolkit, HTML::Parser, …)
  • TK is isolated from the CPAN
  • Moose, DBIx::Class and Catalyst are forming a group. This data are from march, we will try to do a newer version of this map this summer. This one will be really interesting as Catalyst have switched to Moose

The CPAN’s authors

This map is about the authors on the CPAN. There is about 700 authors and their connections. Each time an author use a module of another author, a link is created.

  • Modern Perl, constitued by Moose, Catalyst, DBIx::Class. Important authors are Steven, Sartak, perigin, jrockway, mstrout, nothingmuch, marcus ramberg
  • Slaven Rezić and others TK developpers are on the border
  • Web map

    We crawled the web using the seed generated using the CPAN’s authors pages.

    • again, the “modern group”, on the top of the map, with Moose/Catalyst/DBIx::Class developpers
    • some enterprises, like shadowcat and iinteractive in the middle of the “modern Perl”, Booking in the middle of the YAPC’s websites (they are a major sponsor of this events), 6apart, …
    • is the reference for the Perl community (the site is oriented on their sides)
    • is the reference for the open source community
    • github is in the center of the Perl community. It’s widely adopted by the Perl developpers. It offers all the “social media” features that are missing on the CPAN

    We hope you like this visualisations, have fun analyzing them 🙂

    Thanks Franck for the original post.