networkx - change color/width according to edge attributes - inconsistent result

Question

I managed to produce the graph correctly, but with some more testing noted inconsistent result for the following two different line of codes:

colors = [h.edg         


        

Answer 1

Dictionaries are the underlying data structure used for NetworkX graphs, and as of Python 3.7+ they maintain insertion order. This means that we can safely use nx.get_edge_attributes to retrieve edge attributes since we are guaranteed to have the same edge order in every run of Graph.edges() (which is internally called by get_edge_attributes).

So when plotting, we can directly set attributes such as edge_color and width from the result returned by get_edge_attributes. Here's an example:

G = nx.Graph()
G.add_edge(0,1,color='r',weight=2)
G.add_edge(1,2,color='g',weight=4)
G.add_edge(2,3,color='b',weight=6)
G.add_edge(3,4,color='y',weight=3)
G.add_edge(4,0,color='m',weight=1)

colors = nx.get_edge_attributes(G,'color').values()
weights = nx.get_edge_attributes(G,'weight').values()

pos = nx.circular_layout(G)
nx.draw(G, pos, 
        edge_color=colors, 
        width=list(weights),
        with_labels=True,
        node_color='lightgreen')