Graph loading, dumping, and sampling

Beyond NetworkX, graphs and networks can be generated and analyzed with other software. One of the best open source multi-platform software that can be used for their analysis is named Gephi. It's a visual tool and it doesn't require programming skills. It's freely available at http://gephi.github.io.

As in machine learning datasets, even graphs have standard formats for their storing, loading, and exchanging. In this way, you can create a graph with NetworkX, dump it to a file, and then load and analyze it with Gephi.

One of the most frequently used formats is Graph Modeling Language (GML). Now, let's see how to dump a graph to GML file:

In:
dump_file_base = "dumped_graph"
# Be sure the dump_file file doesn't exist
def remove_file(filename):
    import os
    if os.path.exists(filename):
        os.remove(filename)

In: G = nx.krackhardt_kite_graph()

In:
# GML format write and read
GML_file = dump_file_base + '.gml'
remove_file(GML_file)

nx.write_gml...