import matplotlib failing on Heroku

Question

[(Basically identical to this from a few months ago: import matplotlib failing with No module named _tkinter on heroku . However, the only solution provided doesn't seem to work. (Unfortunately I can't comment on the answer given there since I don't have enough StackOverflow reputation.))]

I've been plotting using matplotlib in my app. Everything works fine locally. However when I push my app to Heroku I get the error:

import _tkinter # If this fails your Python may not be configured for Tk
ImportError: No module named _tkinter

I've tried to circumvent Tkinter by doing:

import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt, mpld3

However this still throws the same error.

Has anyone found a solution for this or have a Heroku app with matplotlib that is working? I'm running Python 2.7.13 (that's also the version Heroku installs when pushing the app).

Answer 1

For me this works:

Change the matplotlib backend from tkinter to something else. At the very beginning of the program do this:

import matplotlib
matplotlib.use('Agg')

This way the rest of the program will use the backend that you set ('Agg', 'SVG', etc, etc)

Another option would be to try and mess with the The matplotlibrc file per: https://matplotlib.org/users/customizing.html#the-matplotlibrc-file