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

To make sure your code is portable across Windows, Linux and OSX and for systems with and without displays, I would suggest following snippet:

import matplotlib
import os
# must be before importing matplotlib.pyplot or pylab!
if os.name == 'posix' and "DISPLAY" not in os.environ:
    matplotlib.use('Agg')

# now import other things from matplotlib
import matplotlib.pyplot as plt

Credit: https://stackoverflow.com/a/45756291/207661