ForceAtlas2 1.0

The ForceAtlas2 algorithm for Python (and NetworkX)

This is a port of Gephi’s ForceAtlas2 layout algorithm to Python 2 and Python 3 (with a wrapper for NetworkX).

Installation

The only strict dependency is Numpy. Cython is highly recommended, as it will speed it up by a factor of 10-100, depending on the graph. Both can be installed with:

pip install numpy pip install cython

To use the NetworkX wrapper function, you obviously need NetworkX.

Then to install this package, it is the typical:

python setup.py install

Example usage

Two core functions are defined:

• forceatlas2.forceatlas2 takes an adjacency matrix and optionally initial positions and other optional arguments. It uses this to calculate a layout.

• forceatlas2.forceatlas2_networkx_layout takes a NetworkX graph and returns a NetworkX-compatible layout.

To use within NetworkX:

import matplotlib.pyplot as plt import networkx import random import forceatlas2 G = networkx.karate_club_graph() pos = { i : (random.random(), random.random()) for i in G.nodes()} # Optionally specify positions as a dictionary l = forceatlas2.forceatlas2_networkx_layout(G, pos, niter=1000) # Optionally specify iteration count networkx.draw_networkx(G, l) plt.show()

Note that my coding style is non-Pythonic, as I don’t use function docstrings. You will have to take a look at the function definition in forceatlas2.py to see a description of all of the potential arguments.

Copyright

These files are Copyright 2016 Max Shinn <[e-mail]> and available under the GNU GPLv3. They are heavily based on the java files included in Gephi, revision git revision 1fba8c1. The (not so clear?) copyright information included in the files I this module is based on are:

Copyright 2008-2011 Gephi Authors : Mathieu Jacomy <[e-mail]> Website : http://www.gephi.org Copyright 2011 Gephi Consortium. All rights reserved. Portions Copyrighted 2011 Gephi Consortium.

The contents of this file are subject to the terms of either the GNU General Public License Version 3 only (“GPL”) or the Common Development and Distribution License(“CDDL”) (collectively, the “License”). You may not use this file except in compliance with the License.