X-Git-Url: https://www.fleuret.org/cgi-bin/gitweb/gitweb.cgi?p=mtp.git;a=blobdiff_plain;f=mtp_graph.h;h=9b342486b18735503697dae564b30d7a1425d9be;hp=9093a8b465d5b4b094d0c8e2cab425db5e2649b0;hb=66479314c7f21ddc2f5e194ad6a25874b2bed909;hpb=fa06c8a9f47351526c626703be5c75591a499f76

diff --git a/mtp_graph.h b/mtp_graph.h
index 9093a8b..9b34248 100644
--- a/mtp_graph.h
+++ b/mtp_graph.h
@@ -37,14 +37,26 @@ class Vertex;
 class Edge;
 
 class MTPGraph {
+  // Uses the estimated vertex distances to the source to make all the
+  // edge lengths positive, resulting in an identical added value to
+  // the total length of any path from source to a certain node (in
+  // particular the sink)
   void update_positivized_lengths();
+
+  // It may happen that numerical errors in update_positivized_lengths
+  // make the resulting lengths negative, albeit very small. The
+  // following method forces all negative lengths to zero, and prints
+  // the total correction when compiled in VERBOSE mode.
   void force_positivized_lengths();
+
   // Set the edge pred_edge_toward_source correspondingly to the path
   // of shortest length. The current implementation is not Dijkstra's!
   void find_shortest_path();
+
   // Follows the path starting on edge e and returns its length. If
   // nodes is non-null, stores in it the nodes met along the path.
   int retrieve_one_path(Edge *e, Path *path);
+
   // Returns if the graph is a DAG
   int is_dag();