Module io

Write the graph G in multiline adjacency list format to the file or file handle path.

See read_multiline_adjlist for file format details.

>>> write_multiline_adjlist(G,"file.adjlist")

path can be a filehandle or a string with the name of the file.

>>> fh=open("file.adjlist")
>>> write_multiline_adjlist(G,fh)

Filenames ending in .gz or .bz2 will be compressed.

>>> write_multiline_adjlist(G,"file.adjlist.gz")

The file will use the default text encoding on your system. It is possible to write files in other encodings by opening the file with the codecs module. See doc/examples/unicode.py for hints.

>>> import codecs
>>> fh=codecs.open("file.adjlist",encoding='utf=8') # use utf-8 encoding
>>> write_multiline_adjlist(G,fh)

Read graph in multi-line adjacency list format from path.

>>> G=read_multiline_adjlist("file.adjlist")

path can be a filehandle or a string with the name of the file.

>>> fh=open("file.adjlist")
>>> G=read_multiline_adjlist(fh)

Filenames ending in .gz or .bz2 will be compressed.

>>> G=read_multiline_adjlist("file.adjlist.gz")

nodetype is an optional function to convert node strings to nodetype

For example

>>> G=read_multiline_adjlist("file.adjlist", nodetype=int)

will attempt to convert all nodes to integer type

Since nodes must be hashable, the function nodetype must return hashable types (e.g. int, float, str, frozenset - or tuples of those, etc.)

edgetype is a function to convert edge data strings to edgetype

>>> G=read_multiline_adjlist("file.adjlist", edgetype=int)

create_using is an optional networkx graph type, the default is Graph(), a simple undirected graph

>>> G=read_multiline_adjlist("file.adjlist", create_using=DiGraph())

The comments character (default='#') at the beginning of a line indicates a comment line.

The entries are separated by delimiter (default=' '). If whitespace is significant in node or edge labels you should use some other delimiter such as a tab or other symbol.

Example multiline adjlist file format:

# source target for Graph or DiGraph
a 2
b
c
d 1
e

or

# source target for XGraph or XDiGraph with edge data a 2 b edge-ab-data c edge-ac-data d 1 e edge-de-data

Reading the file will use the default text encoding on your system. It is possible to read files with other encodings by opening the file with the codecs module. See doc/examples/unicode.py for hints.

>>> import codecs
>>> fh=codecs.open("file.adjlist", encoding='utf=8') # use utf-8 encoding
>>> G=read_multiline_adjlist(fh)

Write graph G in single-line adjacency-list format to path.

See read_adjlist for file format details.

>>> write_adjlist(G, "file.adjlist")

path can be a filehandle or a string with the name of the file.

>>> fh=open("file.adjlist")
>>> write_adjlist(G, fh)

Filenames ending in .gz or .bz2 will be compressed.

>>> write_adjlist(G, "file.adjlist.gz")

The file will use the default text encoding on your system. It is possible to write files in other encodings by opening the file with the codecs module. See doc/examples/unicode.py for hints.

>>> import codecs
>>> fh=codecs.open("file.adjlist",encoding='utf=8') # use utf-8 encoding
>>> write_adjlist(G,fh)

Does not handle data in XGraph or XDiGraph, use 'write_edgelist' or 'write_multiline_adjlist'

Read graph in single line adjacency list format from path.

>>> G=read_adjlist("file.adjlist")

path can be a filehandle or a string with the name of the file.

>>> fh=open("file.adjlist")
>>> G=read_adjlist(fh)

Filenames ending in .gz or .bz2 will be compressed.

>>> G=read_adjlist("file.adjlist.gz")

nodetype is an optional function to convert node strings to nodetype

For example

>>> G=read_adjlist("file.adjlist", nodetype=int)

will attempt to convert all nodes to integer type

Since nodes must be hashable, the function nodetype must return hashable types (e.g. int, float, str, frozenset - or tuples of those, etc.)

create_using is an optional networkx graph type, the default is Graph(), a simple undirected graph

>>> G=read_adjlist("file.adjlist", create_using=DiGraph())

Does not handle edge data: use 'read_edgelist' or 'read_multiline_adjlist'

The comments character (default='#') at the beginning of a line indicates a comment line.

The entries are separated by delimiter (default=' '). If whitespace is significant in node or edge labels you should use some other delimiter such as a tab or other symbol.

# source target a b c d e

Write graph G in edgelist format on file path.

See read_edgelist for file format details.

>>> write_edgelist(G, "file.edgelist")

path can be a filehandle or a string with the name of the file.

>>> fh=open("file.edgelist")
>>> write_edgelist(G,fh)

Filenames ending in .gz or .bz2 will be compressed.

>>> write_edgelist(G, "file.edgelist.gz")

The file will use the default text encoding on your system. It is possible to write files in other encodings by opening the file with the codecs module. See doc/examples/unicode.py for hints.

>>> import codecs
>>> fh=codecs.open("file.edgelist",encoding='utf=8') # use utf-8 encoding
>>> write_edgelist(G,fh)

Read graph in edgelist format from path.

>>> G=read_edgelist("file.edgelist")

path can be a filehandle or a string with the name of the file.

>>> fh=open("file.edgelist")
>>> G=read_edgelist(fh)

Filenames ending in .gz or .bz2 will be compressed.

>>> G=read_edgelist("file.edgelist.gz")

nodetype is an optional function to convert node strings to nodetype

For example

>>> G=read_edgelist("file.edgelist", nodetype=int)

will attempt to convert all nodes to integer type

Since nodes must be hashable, the function nodetype must return hashable types (e.g. int, float, str, frozenset - or tuples of those, etc.)

create_using is an optional networkx graph type, the default is Graph(), a simple undirected graph

>>> G=read_edgelist("file.edgelist",create_using=DiGraph())

The comments character (default='#') at the beginning of a line indicates a comment line.

The entries are separated by delimiter (default=' '). If whitespace is significant in node or edge labels you should use some other delimiter such as a tab or other symbol.

Example edgelist file format:

# source target
a b
a c
d e

or for an XGraph() with edge data

# source target data a b 1 a c 3.14159 d e apple

Write graph object in Python pickle format.

This will preserve Python objects used as nodes or edges.

>>> write_gpickle(G,"file.gpickle")

See cPickle.

Read graph object in Python pickle format

>>> G=read_gpickle("file.gpickle")

See cPickle.

Write graph G in YAML text format to path.

See http://www.yaml.org

Read graph from YAML format from path.

See http://www.yaml.org