Select nodes and edges form networkx graph with attributes

Question

I\'ve just started doing graphs in networkx and I want to follow the evolution of a graph in time: how it changed, what nodes/edges are in the graph at a specified time t.

Answer 1

You may select nodes by conditions with list comprehension with G.nodes() method:

selected_nodes = [n for n,v in G.nodes(data=True) if v['since'] == 'December 2008']  
print (selected_nodes)

Out: [1, 2]

To select edges use G.edges_iter or G.edges methods:

selected_edges = [(u,v) for u,v,e in G.edges(data=True) if e['since'] == 'December 2008']
print (selected_edges)

Out: [(1, 2)]

To plot selected nodes call G.subgraph()

H = G.subgraph(selected_nodes)
nx.draw(H,with_labels=True,node_size=3000)

To plot selected edges with attributes you may construct new graph:

H = nx.Graph(((u, v, e) for u,v,e in G.edges_iter(data=True) if e['since'] == 'December 2008'))
nx.draw(H,with_labels=True,node_size=3000)
plt.show()