Hi,
I am creating an instance of igraph in Python and adding some vertices and edges using add_vertices and add_edges methods of the Graph object. All the vertices and edges are created in one go. I have a 'name' attribute on the vertices and a 'weight' attribute on the edges. Strangely, I am observing multiple edges added between some vertices with the same weight.
Currently I am calling graph.simplify() to remove the unwanted multiple edges after the graph is constructed. But I am wondering why it is creating multiple edges at all. Could someone help me see what might be going on?