python – 从度为> = 3的节点处拆分的图形中检索路径

这是我想出来的,可能不是最快或最优雅的方式,但它应该工作：

import networkx as nx

graph = nx.MultiGraph()
paths = [[1,5],11]]

for path in paths:
    graph.add_path(path)

splitted_paths = []    

# generate list of nodes at which the paths are to be splitted
splitting_nodes = [node for node in graph if graph.degree(node)>=3]

for path in paths:
    # find the splitting nodes in the current path
    splitting_nodes_in_path = [node for node in splitting_nodes if node in path]
    for splitting_node in splitting_nodes_in_path:
        # get remaining path up to the current splitting node
        path_piece = path[:path.index(splitting_node)+1]
        if len(path_piece) > 1:
            splitted_paths.append(path_piece)
        # overwrite current path with the remaining path
        path = path[path.index(splitting_node):]
    # get the remaining piece from the last splitting node until the end of the current path
    if len(path) > 1:        
        splitted_paths.append(path)

print splitted_paths

希望这可以帮助！

编辑1：删除了一个不必要的for循环并添加了一些丢失的代码行

编辑2：如果您需要从图表开始,如@marcus评论建议,并希望在给定的路径列表中有两个路径“粘在一起”,如果它们连接没有度数> = 3的节点,你必须使用不同的方法.我没有时间完全编写我的想法来解决这个问题,但这里是我想要尝试的草图：

>编写一个函数cut(graph,node),它接受Networkx图和nodelabel并逐个节点替换节点(节点)新节点,每个节点连接到一个节点邻居(一个人必须想到一个聪明的方法来命名新节点),所以最终他们来自哪里清楚)
>将cut()应用于度数> = 3的所有节点,最后得到一个断开连接的图形,其中每个组件都是所需的分割路径之一

以下Networkx函数可能对此有用：remove_node(),subgraph(),all_simple_paths(),predecessor()和Operators.