Add script to draw the graph of trajectories

draw_segments.py

+#!/usr/bin/env python3
+
+from graph_tool import draw
+import graph_tool
+import sys
+import pygraphviz as pgv
+import json
+
+g = graph_tool.load_graph(sys.argv[1])
+G = pgv.AGraph(directed = True)
+
+for v in g.vertices():
+    G.add_node(g.vp.name[v])
+
+for e in g.edges():
+    source  = e.source()
+    target = e.target()
+    G.add_edge(g.vp.name[source], g.vp.name[target],
+               penwidth = 10 / g.ep.cost_function[e])
+
+with open("traj_segm.json") as f: traj_segm = json.load(f)
+
+for segment_list in traj_segm:
+    for i in range(len(segment_list) - 1):
+        e = G.get_edge(segment_list[i], segment_list[i + 1])
+        e.attr["color"] = "red"
+
+G.write(sys.argv[2])
+
+G.close()
+# strange failure of the script without this, except in ipython:
+# TypeError: 'NoneType' object is not callable