Plotting networkx graph with node labels defaultin

问题:

NetworkX is powerful but I was trying to plot a graph which shows node labels by default and I was surprised how tedious this seemingly simple task could be for someone new to Networkx. There is an example which shows how to add labels to the plot.

https://networkx.github.io/documentation/latest/examples/drawing/labels_and_colors.html

The problem with this example is that it uses too many steps and methods when all I want to do is just show labels which are same as the node name while drawing the graph.

# Add nodes and edges
G.add_node("Node1")
G.add_node("Node2")
G.add_edge("Node1", "Node2")
nx.draw(G)    # Doesn't draw labels. How to make it show labels Node1, Node2 along?

Is there a way to make nx.draw(G) show the default labels (Node1, Node2 in this case) inline in the graph?

回答1:

tl/dr: just add with_labels=True to the nx.draw call.

So the main reason for the extra complexity on that page was that it is showing how to set lots of different things as the labels as well as give different nodes different colors, and provide careful control over node positions. It appears you just want the name that it was given when the node was created, and you're happy with the default color and default position

import networkx as nx
import pylab as plt

G=nx.Graph()
# Add nodes and edges
G.add_edge("Node1", "Node2")
nx.draw(G, with_labels = True)
plt.savefig('labels.png')

If you wanted to do something so that the node labels were different you could send a dict as an argument. So for example,

labeldict = {}
labeldict["Node1"] = "shopkeeper"
labeldict["Node2"] = "angry man with parrot"

nx.draw(G,labels=labeldict, with_labels = True)