Question

我一直在使用NetworkX来创建MultiDiGraph，在我的练习中，我偶然发现了一个简单的问题，我似乎无法做对。

基本上我想＆＃34;分开＆＃34;添加＆＃34;名称＆＃34;属性随着时间的推移，其关键字在边缘属性中添加时会被保留。我知道＆＃34;名字＆＃34;可能是一个保留字，但从下面的代码中看到，边数据仍然可以包含关键字＆＃34; name＆＃34;没有问题。

最后一个是我想要完成的事情。

#trying to update edge between 1,2 where there is still no 'name' attribute
G.edge[1][2]['name']='Lacuña'

#trying to add another edge to test if it will get the 'name' keyword
G.add_edge(9,10,name = 'Malolos')
print("\nNODES: " + str(G.nodes()))
print("EDGES: " + str(G.edges(data=True)))

输出：

NODES: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
EDGES: [(1, 2, {}), (1, 2, 'Lacu\xc3\xb1a'), 
(4, 5, {'number': 282}), (4, 5, {'route': 37}), 
(5, 4, {'number': '117'}), (6, 7, {}), 
(7, 8, {}), (8, 9, {}), (9, 10, {'name': 'Malolos'})]

问题1：

G.edge[1][2]['name']='Lacuña'

不更新边缘数据。而是使用属性值

问题2：

不会创建类似于(9, 10, {'name': 'Malolos'})的输出，其中关键字＆＃39; name＆＃39;出现在属性dict

如何使用单个属性更新现有单边关键字＆＃39; name＆＃39;并且仍然出现在edge属性dict中？

提前谢谢！

Answer 1

你想：

G[1][2]['name'] = 'Lacuña'

示例：

import networkx as nx
G = nx.Graph()
G.add_edge(1,2)
G[1][2]['name'] = 'Lacuña'
G.edges(data=True)

Out[1]: [(1, 2, {'name': 'Lacuña'})]

Answer 2

I guess this will beneficial to beginners who might've overlooked between using DiGraph and MultiDiGraphs.

Problem 1 : Does not update edge data. Instead creates another edge with attribute value.

Given the code :

G.edge[1][2]['name']='Lacuña' creates another edge instance and not in key-value pair,

while

G[1][2]['name']='Lacuña', will result to an error, in 'name'

Answer : MultiDiGraphs use G[u][v][key] format instead of the default G[u][v] for DiGraphs. Therefore when updating above, ['name'] was considered as a key which was not found; creating a new edge with that key and not as an attribute.

So to update a MultiDiGraph edge and add an attribute. The code should be like this:

G[1][2][0]['name'] = 'Lacuña' #where 0 is an incremental integer if not set
G.edges(data=True)

Out[1]: [(1, 2, 0, {'name': 'Lacuña'})]

While @harryscholes answer is how to update DiGraphs.

Python Networkx如何更新边缘添加＆＃39; name＆＃39;作为一个属性？

2 个答案: