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
|
# Copyright (C) 2011 by
# Aric Hagberg <hagberg@lanl.gov>
# Dan Schult <dschult@colgate.edu>
# Pieter Swart <swart@lanl.gov>
# All rights reserved.
# BSD license.
from itertools import count,repeat
import json
import networkx as nx
__author__ = """Aric Hagberg (hagberg@lanl.gov))"""
__all__ = ['tree_data',
'tree_graph']
def tree_data(G, root):
"""Return data in tree format that is suitable for JSON serialization
and use in Javascript documents.
Parameters
----------
G : NetworkX graph
G must be an oriented tree
root : node
The root of the tree
Returns
-------
data : dict
A dictionary with node-link formatted data.
Examples
--------
>>> from networkx.readwrite import json_graph
>>> G = nx.DiGraph([(1,2)])
>>> data = json_graph.tree_data(G,root=1)
To serialize with json
>>> import json
>>> s = json.dumps(data)
Notes
-----
Node attributes are stored in this format but keys
for attributes must be strings if you want to serialize with JSON.
Graph and edge attributes are not stored.
See Also
--------
tree_graph, node_link_data, node_link_data
"""
if not G.number_of_nodes()==G.number_of_edges()+1:
raise TypeError("G is not a tree.")
if not G.is_directed():
raise TypeError("G is not directed")
def add_children(n, G):
nbrs = G[n]
if len(nbrs) == 0:
return []
children = []
for child in nbrs:
d = dict(id=child, **G.node[child])
c = add_children(child,G)
if c:
d['children'] = c
children.append(d)
return children
data = dict(id=root, **G.node[root])
data['children'] = add_children(root,G)
return data
def tree_graph(data):
"""Return graph from tree data format.
Parameters
----------
data : dict
Tree formatted graph data
Returns
-------
G : NetworkX DiGraph
Examples
--------
>>> from networkx.readwrite import json_graph
>>> G = nx.DiGraph([(1,2)])
>>> data = json_graph.tree_data(G,root=1)
>>> H = json_graph.tree_graph(data)
See Also
--------
tree_graph, node_link_data, adjacency_data
"""
graph = nx.DiGraph()
def add_children(parent, children):
for data in children:
child = data['id']
graph.add_edge(parent, child)
grandchildren = data.get('children',[])
if grandchildren:
add_children(child,grandchildren)
nodedata = dict((str(k),v) for k,v in data.items()
if k!='id' and k!='children')
graph.add_node(child,attr_dict=nodedata)
root = data['id']
children = data.get('children',[])
nodedata = dict((k,v) for k,v in data.items()
if k!='id' and k!='children')
graph.add_node(root, attr_dict=nodedata)
add_children(root, children)
return graph
|