使用networkx添加边缘

Question

Are there any easy method to add a large number of edges together in networkx

I want to add edges from a list.

Answer 1

Assuming that by "add a large number of edges together" you mean "add them to a graph", from help(networkx.Graph) :

 |  **Edges:**
 |  
 |  G can also be grown by adding edges.
 |  
 |  Add one edge,
 |  
 |  >>> G.add_edge(1, 2)
 |  
 |  a list of edges,
 |  
 |  >>> G.add_edges_from([(1,2),(1,3)])

And so:

>>> import networkx as nx
>>> g = nx.Graph()
>>> g.add_edges_from([(0,4),(1,2),(2,3)])
>>> g
<networkx.classes.graph.Graph object at 0x1004b58d0>
>>> g.edges()
[(0, 4), (1, 2), (2, 3)]

I would definitely recommend getting in the habit of reading the interactive documentation. I was using IPython , and so all I had to do to quickly skim the available methods was make a graph g , and then type g.[TAB] . This brought up a list, and g.add_edges_from was #3.

OTOH, if you simply want to add two lists of edges together, you can do that too:

>>> g0.edges() + g1.edges()
[(1, 2), (2, 3), (3, 4), (1, 2), (2, 3), (3, 4), (5, 6)]
>>> set(g0.edges() + g1.edges())
set([(1, 2), (3, 4), (5, 6), (2, 3)])

Answer 2

Often graph data is stored in a file, which makes it easy to read with Pandas dataframe. For example, consider constructing a graph for a seventh grader network . We can initialize our graph as follows:

import pandas as pd
import networkx as nx

#read the edge list
edges = pd.read_csv('./data/moreno_seventh/out.moreno_seventh_seventh', skiprows=2, sep = " ", header=None)
edges.columns = ['student1', 'student2', 'count']

#read node metadata
meta =pd.read_csv('./data/moreno_seventh/ent.moreno_seventh_seventh.student.gender', header=None)
meta.index += 1
meta.columns = ['gender']

#construct the graph
G = nx.DiGraph()
for row in edges.iterrows():
    G.add_edge(row[1]['student1'], row[1]['student2'], count=row[1]['count'])

#add meta data
for i in G.nodes():
    G.node[i]['gender'] = meta.ix[i]['gender']