“UserWarning: Matplotlib is currently using agg, which is a non-GUI backend, so cannot show the figure.” when plotting figure with pyplot on Pycharm

问题

I am trying to plot a simple graph using pyplot, e.g.:

import matplotlib.pyplot as plt
plt.plot([1,2,3],[5,7,4])
plt.show()

but the figure does not appear and I get the following message:

UserWarning: Matplotlib is currently using agg, which is a non-GUI backend, so cannot show the figure.

I saw in several places that one had to change the configuration of matplotlib using the following:

import matplotlib
matplotlib.use('TkAgg')
import matplotlib.pyplot as plt

I did this, but then got an error message because it cannot find a module:

ModuleNotFoundError: No module named 'tkinter'

Then, I tried to install "tkinter" using pip install tkinter (inside the virtual environment), but it does not find it:

Collecting tkinter
  Could not find a version that satisfies the requirement tkinter (from versions: )
No matching distribution found for tkinter

I should also mention that I am running all this on Pycharm Community Edition IDE using a virtual environment, and that my operating system is Linux/Ubuntu 18.04.

I would like to know how I can solve this problem in order to be able to display the graph.

回答1:

I found a solution to my problem (thanks to the help of ImportanceOfBeingErnest).

All I had to do was to install tkinter through the Linux bash terminal using the following command:

sudo apt-get install python3-tk

instead of installing it with pip or directly in the virtual environment in Pycharm.

回答2:

In my case, the error message was implying that I was working in a headless console. So plt.show() could not work. What worked was calling plt.savefig:

import matplotlib.pyplot as plt

plt.plot([1,2,3], [5,7,4])
plt.savefig("mygraph.png")

I found the answer on a github repository.

回答3:

If you use Arch Linux (distributions like Manjaro or Antegros) simply type:

sudo pacman -S tk

And all will work perfectly!

回答4:

Try import tkinter because pycharm already installed tkinter for you, I looked Install tkinter for Python

You can maybe try:

import tkinter
import matplotlib
matplotlib.use('TkAgg')
plt.plot([1,2,3],[5,7,4])
plt.show()

as a tkinter-installing way

I've tried your way, it seems no error to run at my computer, it successfully shows the figure. maybe because pycharm have tkinter as a system package, so u don't need to install it. But if u can't find tkinter inside, you can go to Tkdocs to see the way of installing tkinter, as it mentions, tkinter is a core package for python.

回答5:

I too had this issue in PyCharm. This issue is because you don't have tkinter module in your machine.

To install follow the steps given below (select your appropriate os)

For ubuntu users

 sudo apt-get install python-tk

or

 sudo apt-get install python3-tk

For Centos users

 sudo yum install python-tkinter

or

 sudo yum install python3-tkinter

For Windows, use pip to install tk

After installing tkinter restart your Pycharm and run your code, it will work

来源：https://stackoverflow.com/questions/56656777/userwarning-matplotlib-is-currently-using-agg-which-is-a-non-gui-backend-so