networkx directed graph can't add weight in the middle of the edges from pandas df-CodePudding

My dataframe columns are A,B,Weight. Around 50 rows

Here is my code

G = nx.from_pandas_edgelist(df, source='A',
                                target='B',
                                create_using=nx.DiGraph())
weight = nx.get_edge_attributes(G, 'Weight')
pos = nx.circular_layout(G, scale=1)
nx.draw(G, pos, with_labels=True)
nx.draw_networkx_nodes(G, pos, node_size=300)
nx.draw_networkx_edges(G, pos=pos, edgelist=G.edges(), edge_color='black')
nx.draw_networkx_labels(G, pos=pos, edge_labels=weight)
plt.show()

It can generate a directed graph that has many edges, and connect A to B. But it still can't display the weight in the middle of the edge, What should I do?

CodePudding user response：

There are two errors that prevented this. First, you need to assign the edge attributes to the graph when defining it. Second, you need to use nx.draw_networkx_edge_labels() and not nx.draw_networkx_labels(). The latter is for node labels, not edge labels.

import pandas as pd
import networkx as nx

df = pd.DataFrame([[1, 2, 4], [3, 4, 2], [1, 3, 1]], columns=['A', 'B', 'Weight'])

G = nx.from_pandas_edgelist(df, source='A',
                                target='B',
                                create_using=nx.DiGraph(),
                                edge_attr='Weight')
weight = nx.get_edge_attributes(G, 'Weight')
pos = nx.circular_layout(G, scale=1)
nx.draw(G, pos, with_labels=True)
nx.draw_networkx_nodes(G, pos, node_size=300)
nx.draw_networkx_edges(G, pos=pos, edgelist=G.edges(), edge_color='black')
nx.draw_networkx_edge_labels(G, pos=pos, edge_labels=weight)
plt.show()

plots