Visualize metaballs

Following the article Nodes groups visualization I was trying to implement this work in the new (very) experimental 0.7 version, just for fun. The purpose of this Potatoes module is to enable users to highlight group of nodes in a network.

When clustering (i.e. grouping) nodes, it is useful to leverage group perception on the network visualization. For instance with SNA (Social Network Analysis) it is a good way to display communities and better see interactions between them.

However it is a difficult problem, both for a software designer and a developer. There is no perfect way to visualize groups when the number of them increases and when they starts to hide and blend each other. This problem appears especially when using convex hulls solution. The presented solution belongs to implicit surfaces systems, also called Metaballs. I found the visual result very precise and beautiful, some qualify it organic. Unfortunately it costs much more resources than hulls to calculate these potatoes and may be applied only on small graphs.

Here you can see a very good example of this feature.

Export from Gephi with metaballs

The following video presents it with movement. A small network is displayed with 3 different groups, one per color. A spatialization algorithm is running and moves nodes according to their links. Metaballs are refreshed continuously when moving.

http://vimeo.com/moogaloop.swf?clip_id=4551215&server=vimeo.com&show_title=1&show_byline=0&show_portrait=0&color=59a5d1&fullscreen=1
Gephi – Potatoes work in progress from gephi on Vimeo.

Conclusions of this experimental implementation will guide us for official specification of further Gephi releases. We will implement this functionality for vectorial export but presumably not in the 3d engine.

4 Comments

  1. Is there a tutorial on how to visually create something like this? I’ve got some data that has obvious groupings but would like some instructions on how to get it looking like you have above…

    Reply

    1. No, this was an experimental feature in Gephi 0.6. We didn’t included because it has too bad performances (lag over 50 nodes), but you may use the convex hulls generated over a hierarchical graphs in Gephi 0.7. We will add some tutorials asap.

      Reply

  2. Dear All,

    I am a PhD Student at Lancaster University UK.

    As part of my research I am considering to observe overtime the role that metaphors play in a Social Network Learning Environment and I would very much leverage on Gephi for that.

    I am particularly intrigued by Gephi-Potatoes dynamic visualization (http://vimeo.com/4551215). The Social Network I will focus on (created via GRO.UP) will include about 40 individuals exchanging posts on a learning experience they are all involved in.

    In practice what I am considering is to apply a Forced Metaphors Elicitation procedures on the above participants and start from that to:

    1) cluster participants on the basis of key characteristics of their leading individual metaphors,

    2) follow how the social network (nodes being the individuals and links the interactions) and metaphors (hopefully represented by potatoes) evolve over a period of 12 months,

    3) assess how metaphors and network will be changed by the end of the experience,

    4) cross check if there is any correlation between the above measurements and level of satisfaction expressed by participants to each session of the learning initiative they are living and their levels of attainment.

    As you can see there are a lot of variables I would like to take into consideration. The support of good tools as Gephi-Potatoes seems to be is likely to be crucial.

    I will be grateful for any suggestion and support.

    Bye,

    Luca

    Reply

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