When calculating an empty graph, the modularity calculation throw this error:

java.lang.ArithmeticException: / by zero
at org.gephi.statistics.plugin.Modularity.execute(Modularity.java:477)
at org.gephi.statistics.plugin.Modularity.execute(Modularity.java:454)
at bitcoinvisualizer.GraphExporter.Export(GraphExporter.java:529)
at bitcoinvisualizer.GraphExporter.ExportBetweenTwoDates(GraphExporter.java:188)
at bitcoinvisualizer.GraphExporter.ExportOwnersAndDaysToMysql(GraphExporter.java:165)
at bitcoinvisualizer.Main.main(Main.java:83)

Modularity was invoked using this method:

// Modularity
LOG.info("Begin Modularity...");
Modularity modularity = new Modularity();
modularity.setRandom(true);
modularity.setUseWeight(true);
modularity.setResolution(1.0);
modularity.execute(graphModel, attributeModel);
LOG.info("Modularity Complete.");