In read_overlap.py, plot with dot from Graphviz.

Tests/read_overlap.py

@@ -18,6 +18,8 @@ with open("edgelist_1.csv") as f:
                                  int(row[3]), float(row[4])
         G.add_edge((k1, i1), (k2, i2), weight = weight)
 
+pos = nx.nx_agraph.graphviz_layout(G, prog="dot")
+
 plt.figure()
-nx.draw(G, with_labels=True)
+nx.draw(G, pos, with_labels=True)
 plt.show()