<p>Community detection algorithms are sometimes part of a library (such as <a href="http://jung.sourceforge.net/">JUNG</a> for java) or a tool (see <a href="http://gephi.org/">Gephi</a>). When authors publish a new method, they do sometimes make their code available. For example, the <a href="http://sites.google.com/site/findcommunities/">Louvain</a> and <a href="http://www.mapequation.org/mapdemo/index.html">Infomap</a> methods.</p>

<p>Side note: Girvan-Newman algorithm is sometimes still used, but it has mostly been replaced by faster and more accurate methods. For a good overview of the topic, I recommend <a href="http://arxiv.org/abs/0908.1062">Community detection algorithms: a comparative analysis</a> or the longer <a href="http://arxiv.org/abs/0906.0612">Community detection in graphs</a> (103 pages).</p>
Are there implementations of algorithms for community detection in graphs?
<p>I am looking for implementations of community detection algorithms, such as the Girvan-Newman algorithm (2002). I have visited the websites of several researchers in this field (Newman, Santo, etc.) but was unable to find any code. I imagine someone out there published implementations of these algorithms (maybe even a toolkit?), but I can't seem to find it.</p>