Networkx: convert a MultiDiGraph to DiGraph

Question

Is there a quick method to convert a networkx MultiDiGraph object to DiGraph? I am creating a scale_free_graph using this code:

import networkx as nx
G = nx.scale_free_graph(100)

But I would like to remove all self loops and parallel edges from my graph.

Answer 1

You can create the new nx.DiGraph using the nx.MultiDiGraph as input graph:

incoming_graph_data (input graph (optional, default: None)) – Data to initialize graph. If None (default) an empty graph is created. The data can be an edge list, or any NetworkX graph object. If the corresponding optional Python packages are installed the data can also be a NumPy matrix or 2d ndarray, a SciPy sparse matrix, or a PyGraphviz graph.

import networkx as nx

G = nx.MultiDiGraph()
G.add_edges_from([
    (1, 2),
    (1, 2),
    (1, 2)
])
print('G edges:', G.edges)
H = nx.DiGraph(G)
print('H edges:', H.edges)

Will print:

G edges: [(1, 2, 0), (1, 2, 1), (1, 2, 2)]
H edges: [(1, 2)]