Rename n2 to v2 and n3 to v3

So the comparison with `segments.py` is easier.

Trajectories/Tests/segments_networkx.py

@@ -15,21 +15,21 @@ for v in g: g.nodes[v]["inst_eddies"] = [v]
         
 for v in g:
     if g.in_degree[v] == 1:
-        n2 = next(g.predecessors(v))
+        v2 = next(g.predecessors(v))
 
-        if g.out_degree[n2] == 1:
+        if g.out_degree[v2] == 1:
             # v continues a segment, circumvent v:
 
             nbunch.append(v)
-            g.remove_edge(n2, v)
+            g.remove_edge(v2, v)
 
-            for n3 in list(g.successors(v)):
-                g.remove_edge(v, n3)
-                g.add_edge(n2, n3)
+            for v3 in list(g.successors(v)):
+                g.remove_edge(v, v3)
+                g.add_edge(v2, v3)
 
             # Add the segments represented by v to the segments
-            # represented by n2:
-            g.nodes[n2]["inst_eddies"] += g.nodes[v]["inst_eddies"]
+            # represented by v2:
+            g.nodes[v2]["inst_eddies"] += g.nodes[v]["inst_eddies"]
 
 g.remove_nodes_from(nbunch)
 for k in sorted(g.nodes): print(k, g.nodes[k])