Re: [Boost-bugs] [Boost C++ Libraries] #11137: Bug in graph/dijkstra_shortest_paths_no_color_map.hpp

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #11137: Bug in graph/dijkstra_shortest_paths_no_color_map.hpp
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-03-24 13:11:14

#11137: Bug in graph/dijkstra_shortest_paths_no_color_map.hpp
-------------------------------+----------------------
  Reporter:  hokix@…           |      Owner:  jewillco
      Type:  Bugs              |     Status:  new
 Milestone:  To Be Determined  |  Component:  graph
   Version:  Boost 1.57.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+----------------------

Comment (by anonymous):

 Replying to [ticket:11137 hokix@…]:
 > Hi,
 >
 > I'm a new user to Boost Graph Library and I'm just start to figure out
 how to use it. So I apologize if I'm wrong.
 >
 > While testing dijkstra algorithm, I found a possible bug in
 > graph/dijkstra_shortest_paths_no_color_map.hpp.
 >
 > In function dijkstra_shortest_paths_no_color_map_no_init, the code does
 not initialize distance_map[start_vertex] to 0 before push it into
 vertex_queue, as the document says here
 http://www.boost.org/doc/libs/1_57_0/libs/graph/doc/dijkstra_shortest_paths_no_color_map.html

 >
 > So this will always return at the start vertex if the distance_map is
 initialized to infinity:
 >
 > {{{
 > if (!distance_compare(min_vertex_distance, distance_infinity)) {
 > // This is the minimum vertex, so all other vertices are unreachable
 > return;
 > }
 > }}}
 >
 >
 >
 > Hui Xiao

 I'm sorry, I didn't notice that the initialization is in function
 dijkstra_shortest_paths_no_color_map and I have to init
 distance_map[start_vertex] to 0 myself.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11137#comment:1>
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