获取包含一定数量节点的networkx子图

Question

我有一个 networkx 有向图，我想提取包含一定数量节点的子图。例如，有向图是 0-1-2-3-4-5。我想获取所有包含3个节点的子图。结果应该是：0-1-2、1-2-3、2-3-4、3-4-5。我怎样才能做到这一点？

Answer 1

我不完全确定我是否理解正确：你的例子意味着你只想要连接的子图？在有向图中，存在不止一种连接（弱连接和强连接）。因此，您必须决定要寻找哪一个。这可能有效：import networkx as nxfrom itertools import combinations# The graph in your example (as I understand it)G = nx.DiGraph((i, i+1) for i in range(5))num_of_nodes = 3 # Number of nodes in the subgraphs (here 3, as in your example)subgraphs = [] # List for collecting the required subgraphsfor nodes in combinations(G.nodes, num_of_nodes):    G_sub = G.subgraph(nodes) # Create subgraph induced by nodes    # Check for weak connectivity    if nx.is_weakly_connected(G_sub):        subgraphs.append(G_sub)combinations(G.nodes, num_of_nodes)迭代num_of_nodes来自 的许多节点的所有唯一组合G。所选的子图正是您提到的：print([H.nodes for H in subgraphs])print([H.edges for H in subgraphs])节目[NodeView((0, 1, 2)), NodeView((1, 2, 3)), NodeView((2, 3, 4)), NodeView((3, 4, 5))][OutEdgeView([(0, 1), (1, 2)]), OutEdgeView([(1, 2), (2, 3)]), OutEdgeView([(2, 3), (3, 4)]), OutEdgeView([(3, 4), (4, 5)])]如果你的图表是G = nx.DiGraph([(i, i+1) for i in range(5)] + [(i+1, i) for i in range(5)])如果您正在寻找强大的连接性，那么您必须使用...    # Check for strong connectivity    if nx.is_strongly_connected(G_sub):        ...（通常的警告：G.subgraph()只给你一个视图。）