/usr/lib/python3/dist-packages/networkx/relabel.py is in python3-networkx 1.11-1ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 | # Copyright (C) 2006-2013 by
# Aric Hagberg <hagberg@lanl.gov>
# Dan Schult <dschult@colgate.edu>
# Pieter Swart <swart@lanl.gov>
# All rights reserved.
# BSD license.
import networkx as nx
__author__ = """\n""".join(['Aric Hagberg <aric.hagberg@gmail.com>',
'Pieter Swart (swart@lanl.gov)',
'Dan Schult (dschult@colgate.edu)'])
__all__ = ['convert_node_labels_to_integers', 'relabel_nodes']
def relabel_nodes(G, mapping, copy=True):
"""Relabel the nodes of the graph G.
Parameters
----------
G : graph
A NetworkX graph
mapping : dictionary
A dictionary with the old labels as keys and new labels as values.
A partial mapping is allowed.
copy : bool (optional, default=True)
If True return a copy, or if False relabel the nodes in place.
Examples
--------
>>> G=nx.path_graph(3) # nodes 0-1-2
>>> mapping={0:'a',1:'b',2:'c'}
>>> H=nx.relabel_nodes(G,mapping)
>>> print(sorted(H.nodes()))
['a', 'b', 'c']
>>> G=nx.path_graph(26) # nodes 0..25
>>> mapping=dict(zip(G.nodes(),"abcdefghijklmnopqrstuvwxyz"))
>>> H=nx.relabel_nodes(G,mapping) # nodes a..z
>>> mapping=dict(zip(G.nodes(),range(1,27)))
>>> G1=nx.relabel_nodes(G,mapping) # nodes 1..26
Partial in-place mapping:
>>> G=nx.path_graph(3) # nodes 0-1-2
>>> mapping={0:'a',1:'b'} # 0->'a' and 1->'b'
>>> G=nx.relabel_nodes(G,mapping, copy=False)
print(G.nodes())
[2, 'b', 'a']
Mapping as function:
>>> G=nx.path_graph(3)
>>> def mapping(x):
... return x**2
>>> H=nx.relabel_nodes(G,mapping)
>>> print(H.nodes())
[0, 1, 4]
Notes
-----
Only the nodes specified in the mapping will be relabeled.
The keyword setting copy=False modifies the graph in place.
This is not always possible if the mapping is circular.
In that case use copy=True.
See Also
--------
convert_node_labels_to_integers
"""
# you can pass a function f(old_label)->new_label
# but we'll just make a dictionary here regardless
if not hasattr(mapping,"__getitem__"):
m = dict((n, mapping(n)) for n in G)
else:
m = mapping
if copy:
return _relabel_copy(G, m)
else:
return _relabel_inplace(G, m)
def _relabel_inplace(G, mapping):
old_labels = set(mapping.keys())
new_labels = set(mapping.values())
if len(old_labels & new_labels) > 0:
# labels sets overlap
# can we topological sort and still do the relabeling?
D = nx.DiGraph(list(mapping.items()))
D.remove_edges_from(D.selfloop_edges())
try:
nodes = nx.topological_sort(D, reverse=True)
except nx.NetworkXUnfeasible:
raise nx.NetworkXUnfeasible('The node label sets are overlapping '
'and no ordering can resolve the '
'mapping. Use copy=True.')
else:
# non-overlapping label sets
nodes = old_labels
multigraph = G.is_multigraph()
directed = G.is_directed()
for old in nodes:
try:
new = mapping[old]
except KeyError:
continue
if new == old:
continue
try:
G.add_node(new, attr_dict=G.node[old])
except KeyError:
raise KeyError("Node %s is not in the graph"%old)
if multigraph:
new_edges = [(new, new if old == target else target, key, data)
for (_,target,key,data)
in G.edges(old, data=True, keys=True)]
if directed:
new_edges += [(new if old == source else source, new, key, data)
for (source, _, key,data)
in G.in_edges(old, data=True, keys=True)]
else:
new_edges = [(new, new if old == target else target, data)
for (_,target,data) in G.edges(old, data=True)]
if directed:
new_edges += [(new if old == source else source,new,data)
for (source,_,data) in G.in_edges(old, data=True)]
G.remove_node(old)
G.add_edges_from(new_edges)
return G
def _relabel_copy(G, mapping):
H = G.__class__()
H.name = "(%s)" % G.name
if G.is_multigraph():
H.add_edges_from( (mapping.get(n1, n1),mapping.get(n2, n2),k,d.copy())
for (n1,n2,k,d) in G.edges_iter(keys=True, data=True))
else:
H.add_edges_from( (mapping.get(n1, n1),mapping.get(n2, n2),d.copy())
for (n1, n2, d) in G.edges_iter(data=True))
H.add_nodes_from(mapping.get(n, n) for n in G)
H.node.update(dict((mapping.get(n, n), d.copy()) for n,d in G.node.items()))
H.graph.update(G.graph.copy())
return H
def convert_node_labels_to_integers(G, first_label=0, ordering="default",
label_attribute=None):
"""Return a copy of the graph G with the nodes relabeled using
consecutive integers.
Parameters
----------
G : graph
A NetworkX graph
first_label : int, optional (default=0)
An integer specifying the starting offset in numbering nodes.
The new integer labels are numbered first_label, ..., n-1+first_label.
ordering : string
"default" : inherit node ordering from G.nodes()
"sorted" : inherit node ordering from sorted(G.nodes())
"increasing degree" : nodes are sorted by increasing degree
"decreasing degree" : nodes are sorted by decreasing degree
label_attribute : string, optional (default=None)
Name of node attribute to store old label. If None no attribute
is created.
Notes
-----
Node and edge attribute data are copied to the new (relabeled) graph.
See Also
--------
relabel_nodes
"""
N = G.number_of_nodes()+first_label
if ordering == "default":
mapping = dict(zip(G.nodes(), range(first_label, N)))
elif ordering == "sorted":
nlist = G.nodes()
nlist.sort()
mapping = dict(zip(nlist, range(first_label, N)))
elif ordering == "increasing degree":
dv_pairs = [(d,n) for (n,d) in G.degree_iter()]
dv_pairs.sort() # in-place sort from lowest to highest degree
mapping = dict(zip([n for d,n in dv_pairs], range(first_label, N)))
elif ordering == "decreasing degree":
dv_pairs = [(d,n) for (n,d) in G.degree_iter()]
dv_pairs.sort() # in-place sort from lowest to highest degree
dv_pairs.reverse()
mapping = dict(zip([n for d,n in dv_pairs], range(first_label, N)))
else:
raise nx.NetworkXError('Unknown node ordering: %s'%ordering)
H = relabel_nodes(G, mapping)
H.name = "("+G.name+")_with_int_labels"
# create node attribute with the old label
if label_attribute is not None:
nx.set_node_attributes(H, label_attribute,
dict((v,k) for k,v in mapping.items()))
return H
|