I tried the Graph module. I had a deep look at the SPT_Dijkstra algorithm and tried it with some sample data.

I think that I now understand the algorithm. It takes a start vertex and the result are the paths from the start vertex to all other vertices.

But this is not what I need. I need only one path from the start to the end which takes all vertices between into account.

I see no way how to solve my problem with the graph module. Or do I see something wrong? I'll now try another way. Nevertheless thank you. It was interesting to play with this Graph module.

The Graph module does not seem to be the problem, but my lack of knowledge about graph algorithms. I'm reading now about these algorithms. When I understood them, then I'll start my implementation.