Hi!

For the project I'm working on I need to calculate distances on a graph from a couple of vertices to all other vertices. The topology.shortest_distance can only do either from all vertices or from a single one, and to save time I'd like this to run in parallel, so I set out to implement this in C++. I took inspiration from graph-tool's implementation of shortest_distance for pair-wise distances in unweighted graphs (running BFS from all vertices in parallel), and managed to modify that to only run from some vertices. However I ran into a problem trying to do the same for weighted graphs. I think the problem I have is that when passing the vector for distances to all vertices it is supposed to be a property map and not a vector, but I cannot figure out how to get a 1d property map from a 2d property map on a C++ level, basically I pass a vector<double> property map to my function but I need to pass a simple double property map to the dijskstra function from boost. Could anyone please help me point to how would I do that? Or is my approach wrong completely? What most confuses me that the same approach works fine for breadth_first_search.

The errors I'm getting in compilation:

/usr/include/boost/graph/dijkstra_shortest_paths_no_color_map.hpp:43:63: error: no type named ‘value_type’ in ‘struct boost::property_traits<std::vector<double> >’
43 |     typedef typename property_traits<DistanceMap>::value_type Distance;

/usr/include/boost/pending/indirect_cmp.hpp:32:78: error: no type named ‘value_type’ in ‘struct boost::property_traits<std::vector<double> >’
32 |     typedef typename boost::property_traits<ReadablePropertyMap>::value_type T;
|                                                                              ^
/usr/include/boost/pending/indirect_cmp.hpp:33:76: error: no type named ‘key_type’ in ‘struct boost::property_traits<std::vector<double> >’
33 |     typedef typename boost::property_traits<ReadablePropertyMap>::key_type K;

Thank you,

Mikuláš