当网络中节点度为n时合并边

Question

我有一个无向图如下：

import networkx as nx
import matplotlib.pyplot as plt

l = [('1','2'),('2','3'),('3','4'),('3','5'),('1','6'),('6','7'),('6','8'),('9','8')]

G=nx.Graph()
G.add_edges_from(l)
nx.draw_networkx(G,with_labels=True)
plt.show()

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当节点满足degree=n(like 2)时，我想结合边。在我的示例中，我需要删除节点1、2和8，并连接3-6和6-9。因此，我预计结果如下。

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我该怎么做呢？先谢

Answer 1

import networkx as nx
import matplotlib.pyplot as plt

l = [('1','2'),('2','3'),('3','4'),('3','5'),('1','6'),('6','7'),('6','8'),('9','8')]

G=nx.Graph()
G.add_edges_from(l)

# Select all nodes with only 2 neighbors
nodes_to_remove = [n for n in G.nodes if len(list(G.neighbors(n))) == 2]

# For each of those nodes
for node in nodes_to_remove:
    # We add an edge between neighbors (len == 2 so it is correct)
    G.add_edge(*G.neighbors(node))
    # And delete the node
    G.remove_node(node)

nx.draw(G,with_labels=True)

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