Note

This documents the development version of NetworkX. Documentation for the current release can be found here.

networkx.readwrite.edgelist.parse_edgelist

parse_edgelist(lines, comments='#', delimiter=None, create_using=None, nodetype=None, data=True)[source]

Parse lines of an edge list representation of a graph.

Parameters
  • lines (list or iterator of strings) – Input data in edgelist format

  • comments (string, optional) – Marker for comment lines. Default is '#'

  • delimiter (string, optional) – Separator for node labels. Default is None, meaning any whitespace.

  • create_using (NetworkX graph constructor, optional (default=nx.Graph)) – Graph type to create. If graph instance, then cleared before populated.

  • nodetype (Python type, optional) – Convert nodes to this type. Default is None, meaning no conversion is performed.

  • data (bool or list of (label,type) tuples) – If False generate no edge data or if True use a dictionary representation of edge data or a list tuples specifying dictionary key names and types for edge data.

Returns

G – The graph corresponding to lines

Return type

NetworkX Graph

Examples

Edgelist with no data:

>>> lines = ["1 2", "2 3", "3 4"]
>>> G = nx.parse_edgelist(lines, nodetype=int)
>>> list(G)
[1, 2, 3, 4]
>>> list(G.edges())
[(1, 2), (2, 3), (3, 4)]

Edgelist with data in Python dictionary representation:

>>> lines = ["1 2 {'weight': 3}", "2 3 {'weight': 27}", "3 4 {'weight': 3.0}"]
>>> G = nx.parse_edgelist(lines, nodetype=int)
>>> list(G)
[1, 2, 3, 4]
>>> list(G.edges(data=True))
[(1, 2, {'weight': 3}), (2, 3, {'weight': 27}), (3, 4, {'weight': 3.0})]

Edgelist with data in a list:

>>> lines = ["1 2 3", "2 3 27", "3 4 3.0"]
>>> G = nx.parse_edgelist(lines, nodetype=int, data=(("weight", float),))
>>> list(G)
[1, 2, 3, 4]
>>> list(G.edges(data=True))
[(1, 2, {'weight': 3.0}), (2, 3, {'weight': 27.0}), (3, 4, {'weight': 3.0})]