Plotting Networkx graph in Python

Question

I recently started using networkx library in python to generate and visualize graph plots. I started with a simple code (comprising of 4 nodes) as shown

import networkx as nx
import matplotlib.pyplot as plt
G = nx.Graph()
G.add_edges_from([(1 ,2) , (2 ,3) , (1 ,3) , (1 ,4) ])
nx.draw(G)
plt.show()

When I run the code for two consecutive times, the outputs for same code is as shown in the images (the orientation of the plot is random)

Is it possible to generate the output of the plots with the same/fixed orientation?

Answer 1

Per default a spring layout is used to draw the graph. This can have a new orientation each time it is drawn.

There are also other layouts available.

Using e.g. nx.draw_circular or nx.draw_spectral will give you always the same layout.

You may also define the positions of the nodes using a dictionary, which maps nodenumber to a position.

import networkx as nx
import matplotlib.pyplot as plt
G = nx.Graph()
G.add_edges_from([(1 ,2) , (2 ,3) , (1 ,3) , (1 ,4) ])
pos = { 1: (20, 30), 2: (40, 30), 3: (30, 10),4: (0, 40)} 

nx.draw_networkx(G, pos=pos)

plt.show()