How to sum up a networkx graph's edge weights?

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I'm working on a networkx graph project. one of my tasks is to find out the shortest path between two nodes and sumup the weights. I can locate the shortest path, as you may see. However, I have no idea how to sum up the weights of each edge in the shortest path. I think there is going to be a simple function in the package, but I found none. enter image description here

import matplotlib.pyplot as plt
import networkx as nx

def graph(path):
    G = nx.Graph()
    for line in open(path):
        strlist = line.split(',')
        n1 = strlist[0].replace('.0', '')
        n2 = strlist[1].replace('.0', '')
        weight = round(float(strlist[2]), 2)
        G.add_weighted_edges_from([(n1, n2, weight)])

    # labels = dict((i, i) for i in G.nodes())
    # nx.draw_networkx_labels(G, pos=nx.spring_layout(G), labels=labels)
    # plt.savefig(filename)
    elarge = [(u, v) for (u, v, d) in G.edges(data=True) if d["weight"] > 0.5]
    esmall = [(u, v) for (u, v, d) in G.edges(data=True) if d["weight"] <= 0.5]
    pos = nx.spring_layout(G)
    # nodes
    nx.draw_networkx_nodes(G, pos, node_size=200, node_color='#ff0000', alpha=0.9)
    # edges
    nx.draw_networkx_edges(G, pos, edgelist=elarge, width=1, edge_color='b', alpha=0.05)
    nx.draw_networkx_edges(G, pos, edgelist=esmall, width=1, edge_color='b', alpha=0.3)
    edge_labels = nx.get_edge_attributes(G, 'weight')
    nx.draw_networkx_labels(G, pos, font_size=10, font_family="sans-serif")
    nx.draw_networkx_edge_labels(G, pos, edge_labels, font_size=8, font_family='sans-serif')
    plt.axis("off")
    plt.show()
    return G
G = graph('graph.csv')


shortest_value = nx.shortest_path_length(G, source='210', target='2771')
print(shortest_value)
shortest_path = nx.shortest_path(G, source='210', target='2771', method='dijkstra')
print('shortest path：{}'.format(shortest_path))
print('distance：{}'.format(shortest_value))
networkx graph python-3.x
1 Answers

Use networkx.Graph.size.

From the examples:

>>> G = nx.Graph()  # or DiGraph, MultiGraph, MultiDiGraph, etc
>>> G.add_edge("a", "b", weight=2)
>>> G.add_edge("b", "c", weight=4)
>>> G.size()
2
>>> G.size(weight="weight")
6.0
user_57076840
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