Draw a graph with graphviz. This works for directed multigraphs with self loops. Easy to show weights as labels.
from graphviz import Digraph
def drawGraph(mat):
g = Digraph('G', filename='graph.gv')
# G: name allocated to this graph
# filename: used for output file
# mat: weighted adjacency matrix
n = len(mat)
for i in range(n):
for j in range(n):
if mat[i,j] > 0.:
g.edge(str(j),str(i), label=str(mat[i,j]))
# arrow goes j -> i
# label: edge label to show
return g
g = drawGraph(mat)
g.view() # show the graph and save as filename.pdf
