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Rename all nodes in a graph to a sequence of numbers

I am using the NetworkX graph library for Python. At some point in my program I would like to "consolidate" my nodeIDs into a sequence of numbers. Here's my naive approach:

start = 1 # could be anything
for i, n in enumerate(g.nodes()):
    if i+start == n:
        continue
    g.add_node(i+start, attr_dict=g.node[n])
    g.add_edges_from([(i+start, v, g[n][v]) for v in g.neighbors(n)])
    g.remove_node(n)

Is there a faster way than this exhaustive copy of all the neighbors? For example, I tried g[i+start] = g[n], but that is forbidden.

Thanks!

like image 882
Juan Avatar asked Mar 16 '11 00:03

Juan


2 Answers

Would this work?

http://networkx.github.io/documentation/latest/reference/generated/networkx.relabel.convert_node_labels_to_integers.html

import networkx as nx
G = nx.Graph()
G.add_node(1)
G.add_nodes_from('spam')
print G.nodes()

returns:

['a', 1, 's', 'm', 'p']

now:

start = 1
G = nx.convert_node_labels_to_integers(G,first_label=start)
print G.nodes()

returns:

[1, 2, 3, 4, 5]
like image 146
JoshAdel Avatar answered Nov 15 '22 20:11

JoshAdel


In case your interest is still relevant, there is networkx.relabel_nodes() which takes a mapping dictionary.

like image 43
Jason S Avatar answered Nov 15 '22 20:11

Jason S