Networkx: Creating a complete graph for a given set of nodes

Question

I have a list as c4_leaves = [56,78,90,112]. I'm trying to create a complete graph using these elements in c4_leaves as nodes. Here's what I've tried;

    V_ex = c4_leaves
    G_ex = nx.Graph() 
    G_ex.add_nodes_from(V_ex)
    G_ex = nx.complete_graph(4)


    for u,v in G_ex.edges():
        G_ex[u][v]['distance'] = distance(points33, u, v)

And then the minimum spanning tree of the above graph as :

 T_ex= nx.minimum_spanning_tree(G_ex, weight='distance')
 F_ex = list(T_ex.edges())

When I draw G_ex, it gives me the correct graph, but when I print details of the minimum spanning tree, it shows that T_ex.nodes() = [0,1,2,3,56,78,90,112].

Can someone show me the mistake I'm doing?

Answer 1

Instead of using complete_graph, which generates a new complete graph with other nodes, create the desired graph as follows:

import itertools
import networkx as nx

c4_leaves = [56,78,90,112]
G_ex = nx.Graph()
G_ex.add_nodes_from(c4_leaves)
G_ex.add_edges_from(itertools.combinations(c4_leaves, 2))

In the case of directed graphs use:

G_ex.add_edges_from(itertools.permutations(c4_leaves, 2))