networkx: Draw text on edges

Question

for my thesis I need to draw some probabilistic control flow graphs. i.e. control flow graphs with probabilities depicted on the edges.

I found graph-tool which seems quite useful, since it can use deep-copies of existing graphs and my graphs are quite similar.

So my question is, if there is a possibility to draw edge properties (or some strings) on/next to the edges? If it's not possible or highly complicated, is there a tool which is better to use in this case?

Edit: I need directed edges that can even create loops between 2 nodes and have different values. Is there a possibility for this too? So I can see both values? By now I can see the directed graph with a 2-directional edge, but there's only one value on it.

So e.g. in networkx (in reference to Hooked) it would look like:

G = nx.MultiDiGraph()
G.add_edge(0,1)
G.add_edge(1,0)
labels = {(0,1):'foo', (1,0):'bar'}

So that both 'foo' and 'bar' are visible and you can see which direction they are connected to.

But as networkx renders it, I get 1 bidirectional edge with 1 of the labels.

Answer 1

You can draw text next to the edges with graph-tool using "edge_text" option of the graph_draw() function:

from graph_tool.all import *

g = Graph()
g.add_vertex(4)
label = g.new_edge_property("string")
e = g.add_edge(0, 1)
label[e] = "A"
e = g.add_edge(2, 3)
label[e] = "foo"
e = g.add_edge(3, 1)
label[e] = "bar"
e = g.add_edge(0, 3)
label[e] = "gnat"

graph_draw(g, edge_text=label, edge_font_size=40, edge_text_distance=20, edge_marker_size=40, output="output.png")