Unable to "import matplotlib.pyplot as plt" in virtualenv

This solution worked for me. If you already installed matplotlib using pip on your virtual environment, you can just type the following:

$ cd ~/.matplotlib$ nano matplotlibrc

And then, write backend: TkAgg in there. If you need more information, just go to the solution link.

I got the same error, and tried Jonathan's answer:

You can fix this issue by using the backend Agg

Go to User/yourname/.matplotlib and open/create matplotlibrc and add the following line backend : Agg and it should work for you.

I run the program, no error, but also no plots, and I tried backend: Qt4Agg,it prints out that I haven't got PyQt4 installed.

Then I tried another backend: backend: TkAgg, it works!

So maybe we can try difference backends and some may work or install the requeired packages like PyQt4.

Here is a sample python snippet that you can try and test matplotlib.

import matplotlibmatplotlib.use('TkAgg')import matplotlib.pyplot as pltplt.plot([1, 2, 3], [0, 3, 7])plt.show()

I had similar problem when I used pip to install matplotlib. By default, it installed the latest version which was 1.5.0. However, I had another virtual environment with Python 3.4 and matplotlib 1.4.3 and this environment worked fine when I imported matplotlib.pyplot. Therefore, I installed the earlier version of matplotlib using the following:

cd path_to_virtual_environment    # assume directory is called env3env3/bin/pip install matplotlib==1.4.3

I know this is only a work-around, but it worked for me as a short-term fix.