如何仅从邻接矩阵为特定节点创建网络图?

Question

我有一个邻接矩阵 5000X5000，我想创建一个网络图。要求是用户将输入节点，并且输出将是该特定输入节点的图形(1阶和2度(。

我已经尝试使用 Gephi，但由于邻接矩阵很大，我无法专注于每个节点。所以我希望我可以为特定节点创建一个图表(因为我只对每个节点的一度和二度连接感兴趣，而不是超出该范围(

Gephi是基于UI的，所以我没有代码。

输入将是node_id，输出将是对应于该node_id的图形(1度和2度连接(

Answer 1

下面是使用networkx的实现：

import networkx as nx
import numpy as np
# make dummy adjacency matrix
a = np.random.rand(100,100)
a = np.tril(a)
a = a>0.95
# make graph from adjaceny matrix
G = nx.from_numpy_matrix(a)

def neigh(G, node, depth):
""" given starting node, recursively find neighbours
until desired depth is reached
"""
node_list = []
if depth==0:
node_list.append(node)
else:
for neighbor in G.neighbors(node):
node_list.append(node)
node_list += neigh(G, neighbor, depth-1)
return list(set(node_list)) # intermediate conversion to set to lose duplicates. 
# a bit more compressed:
def neigh_short(G, node, depth):
""" given starting node, recursively find neighbours
until desired depth is reached
"""
node_list = [node]
if depth>0:
for neighbor in G.neighbors(node)
node_list += neigh_short(G, neighbor, depth-1)
return list(set(node_list)) # intermediate conversion to set to lose duplicates. 
# example:
# find all neighbours with distance 2 from node 5:
n = neigh(G, node=5, depth=2)
# extract the respective subgraph from G and store in H
H = G.subgraph(n)