Generating a PNG with matplotlib when DISPLAY is undefined

Question

I am trying to use networkx with Python. When I run this program it get this error. Is there anything missing?

#!/usr/bin/env python

import networkx as nx
i         


        

Answer 1

I found this snippet to work well when switching between X and no-X environments.

import os
import matplotlib as mpl
if os.environ.get('DISPLAY','') == '':
    print('no display found. Using non-interactive Agg backend')
    mpl.use('Agg')
import matplotlib.pyplot as plt