你如何在networkx中找到没有传出边的节点？

Question

I am trying to find nodes with no outgoing edges in a digraph in networkx.

Is there a way to do this? I found isolates but that finds edges without incoming or outgoing edges, and I don't want that.

Answer 1

如果G是你的DiGraph ，你可以通过

(node for node, out_degree in G.out_degree_iter() if out_degree == 0)

Answer 2

I had a problem with out_degree_iter() as it returns an error. So I searched for other solutions on NetworkX documentation and found this is working. ( G is a DiGraph )

[node for node in G.nodes if G.out_degree(node) == 0]

Note, in case of finding incoming degree or edges. You can just simply change from out_degree to in_degree

Ref: networkx.DiGraph.out_degree

Answer 3

"methods that returned an iterator have been removed "

in NetworkX 2.x, so @fuglede's answer needs a minor update:

(node for node, out_degree in G.out_degree() if out_degree == 0)

The view/reporting API provided by .out_degree in 2.x provides an OutDegreeView over (node, out_degree) pairs, making this approach slightly simpler than @Fony Lew's.