Font warning: `... font family ['sans-serif'] not found. Falling back to DejaVu Sans ...` when using `fig.canvas.draw()`

[lucainnocenti]

Bug report

Bug summary
Using fig.canvas.draw() to redraw a plot produces the following warning:

/home/myname/anaconda3/lib/python3.6/site-packages/matplotlib/font_manager.py:1297: UserWarning: findfont: Font family ['sans-serif'] not found. Falling back to DejaVu Sans
  (prop.get_family(), self.defaultFamily[fontext]))

It doesn't happen if I just plot the code, only when using fig.canvas.draw() to plot things dynamically.
I experience this when running the code in Anaconda, in bash, in Ubuntu, under Windows 10.
I tried to delete the content of ~/.cache/ (and of the corresponding folder in the windows anaconda installation, just to be sure), but the warning still appears.
I also tried installing font-manager as suggested here, but with no effect.

Code for reproduction

import matplotlib.pyploy as plt
import seaborn
%matplotlib notebook
fig, ax = plt.subplots(1, 1)
ax.plot([0, 1, 2, 3], '-b')
fig.canvas.draw()

Actual outcome

Matplotlib version

• Operating System: Ubuntu in Windows 10 64bit
• Matplotlib Version: 2.0.2
• Python Version: 3.6.1, provided by conda 4.3.2.2
• Jupyter Version: 4.3.0

[lucainnocenti]

Nevermind, the suggestion given here solved the problem: I installed msttcorefonts with
$ sudo apt-get install msttcorefonts -qq
and then deleted the content of .cache/matplotlib and restarted the notebook. No warnings issued anymore.

[tizee]

Nevermind, the suggestion given here solved the problem: I installed msttcorefonts with
$ sudo apt-get install msttcorefonts -qq
and then deleted the content of .cache/matplotlib and restarted the notebook. No warnings issued anymore.

For some Asian fonts, the straight way to solve this problem is that download the font you need and put it in the path like /root/anaconda3/envs/<env name>/lib/python3.7/site-packages/matplotlib/mpl-data/fonts/ttf
and use this maplotlib.matplotlib_fname() to get the path

[lifuqiang2016]

解决了吗？
我的是centos7.5;python3.6 ,出现这个问题

[JustDoItGit]

Nevermind, the suggestion given here solved the problem: I installed msttcorefonts with
$ sudo apt-get install msttcorefonts -qq
and then deleted the content of .cache/matplotlib and restarted the notebook. No warnings issued anymore.

For some Asian fonts, the straight way to solve this problem is that download the font you need and put it in the path like /root/anaconda3/envs/<env name>/lib/python3.7/site-packages/matplotlib/mpl-data/fonts/ttf
and use this maplotlib.matplotlib_fname() to get the path

thanks