write_graph6

write_graph6(G, path, nodes=None, header=True)[source]

Write a simple undirected graph to a path in graph6 format.

Parameters
GGraph (undirected)
pathstr

The path naming the file to which to write the graph.

nodes: list or iterable

Nodes are labeled 0…n-1 in the order provided. If None the ordering given by G.nodes() is used.

header: bool

If True add ‘>>graph6<<’ string to head of data

Raises
NetworkXNotImplemented

If the graph is directed or is a multigraph.

ValueError

If the graph has at least 2 ** 36 nodes; the graph6 format is only defined for graphs of order less than 2 ** 36.

Notes

The function writes a newline character after writing the encoding of the graph.

The format does not support edge or node labels, parallel edges or self loops. If self loops are present they are silently ignored.

References

1

Graph6 specification <http://users.cecs.anu.edu.au/~bdm/data/formats.html>

Examples

You can write a graph6 file by giving the path to a file:

>>> import tempfile
>>> with tempfile.NamedTemporaryFile() as f:
...     nx.write_graph6(nx.path_graph(2), f.name)
...     _ = f.seek(0)
...     print(f.read())
b'>>graph6<<A_\n'