_tkinter.TclError: no display name and no $DISPLAY environment variable

You can solve it by adding these two lines in the VERY beginning of your .py script.

import matplotlib
matplotlib.use('Agg')

PS: The error will still exists if these two lines are not added in the very beginning of the source code.


Matplotlib chooses Xwindows backend by default. You need to set matplotlib to not use the Xwindows backend.

Add this code to the start of your script (before importing pyplot) and try again:

import matplotlib
matplotlib.use('Agg')

Or add to .config/matplotlib/matplotlibrc line backend: Agg to use non-interactive backend.

echo "backend: Agg" > ~/.config/matplotlib/matplotlibrc

Or when connect to server use ssh -X remoteMachine command to use Xwindows.

Also you may try to export display: export DISPLAY=mymachine.com:0.0.

For more info: https://matplotlib.org/faq/howto_faq.html#matplotlib-in-a-web-application-server