title: Is it possible to add undirected and directed edges to a graph object in networkx?
body: <p>I'm working on implementing an algorithm to determine the graphical structure of a dataset. The dataset could have undirected or directed edges between variables. I could create my own graph object in Python, but I was curious if Networkx has this capability. From what I've seen, Networkx only has a Graph object (only undirected edges) and a DiGraph object (for directed edges only). Is there a way to include directed edges in a undirected graph in Networkx and/or vice versa?</p>