Gephi.org | Download Gephi | Blog | Gephi Store | Wiki | Forum | Support | Bugtracker

Look for Gephi Plugins

Popular Keywords

Close Search

OpenOrd Layout

OpenOrd Layout
12 votes, 4.42 avg. rating (88% score)

Introduction

Force-Directed layout algorithm for real-world large-scale undirected graphs.

Plugin Owner’s Notes

It is one of the few force-directed layout algorithms that can scale to over 1 million nodes, making it ideal for large graphs. However, small graphs (hundreds or less) do not always end up looking so good. This algorithm expects undirected weighted graphs and aims to better distinguish clusters. It can be run in parallel to speed up computing.

The algorithm is originally based on Frutcherman-Reingold and works with a fixed number of iterations. The algorithm is using simulated annealing and has five different phases: liquid, expansion, cool-down, crunch, and simmer. Each stage is a fraction of the total iterations and several parameters like temperature, attraction and damping are changing. The default schedule spends approximately 25% of its time in the liquid stage, 25% in the expansion stage, 25% in the cool-down stage, 10% in the crunch stage, and 15% in the simmer stage.

The original OpenOrd C++ implementation is available at the following address : http://www.cs.sandia.gov/~smartin/software.html. This plug-in version doesn’t include the multi-level version of the algorithm. The algorithm was formerly known as DrL, and before that VxOrd.
Parallel

OpenOrd can be run in parallel to speed up computation. Each thread will work on a subset of the nodes of the graph. It’s recommended to put the number of core minus 1 to keep a thread for display. For example on a quad-core computer, it’s good to use three threads.

Edge-Cutting

Edge-cutting in OpenOrd is specified using a fraction from 0 to 1. An edge-cutting value of 0 corresponds to the standard Frutcherman-Reingold layout algorithm (no cutting), while an edge-cutting value of 1 corresponds to aggressive cutting. Aggressive cutting promotes clustering but will not cut every edge. The default value for edge-cutting in OpenOrd is 0.8.

Layout on a grid

Gephi OpenOrd layout on a grid from gephi on Vimeo.

Reference

S. Martin, W. M. Brown, R. Klavans, and K. Boyack (to appear, 2011), “OpenOrd: An Open-Source Toolbox for Large Graph Layout,” SPIE Conference on Visualization and Data Analysis (VDA).

Release history

  • 0.4 (Feb 11): Configure time spent in each stage (liquid, expansion, cool-down, crunch and simmer)
  • 0.3 (Nov 10): First plugin release

Similar Plugins

GC-Viz

The GC-Viz plugin contains the algorithms GAMer and DB-CSC for the clustering of graphs with node attributes. It also contains a layout for visualizing and comparing the clustering results. The plugin has been developed by Brigitte Boden, Roman Haag and Houran Ketabdar. The plugin is described in the following paper: Brigitte Boden, Roman Haag, and [...]

More Info

Maps of Countries

Function of the plugin Use this plugin to insert maps of countries and world regions in Gephi.   Quick instructions – Install the plugin, open a new Project, go to the layout tab and select the layout “Map Of Countries”. – Click on “Run” to load the map of the world.   All features explained [...]

More Info

Layered Layout

This plugin provides layout, where nodes are in different layers (orbits). Assignment of node to layer depends on the value of numerical attribute of node. This layout can very nicely visualize the “Small-World Phenomenon”, where the layer assignement depends on the distance between key node and the others (Erdös number in the SNA Metrics Plugin).

More Info