Hello graphGang! I have some relative simple (but also quiet practical) questions for you. 1. How can you access the indices of the nodes of an arbitrary graph? - You can not assume that they are equal to the "range(graph.num_vertices())”. For instance, imagine that we are dealing with a filtered version of some graph. - Is there another way than invoking the iterator graph.vertices() ? The application I have at hand is to sample pairs of nodes of a graph and apply a function like the shortest distance between them (and I would like to do that fast). 2. I think that when it comes to sampling/accessing of the indices of edges there is not a better way than invoking the iterator graph.edges() and work with its output. Correct? Thanks a lot, H.