python - Matplotlib cannot find basic fonts

Question

I am using matplotlib version 2.0.0 on Python 3 in a miniconda virtual environment. I am working on a unix scientific computing cluster where I don't have root privileges. I am generally executing python code through an ipython notebook. If I do a basic command such as:

import matplotlib.pyplot as plt
plt.scatter([1,5], [1,5])

I get an error message:

path_to_miniconda/miniconda3/envs/conda34/lib/python3.4/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]))

I would like to be able to use a Times New Roman font but even after deleting the Font cache file (fontList.py3k.cache) which I find from here:

import matplotlib as mpl
fm = mpl.font_manager
fm.get_cachedir()

The commands:

mpl.rcParams['font.family'] = ['serif']
mpl.rcParams['font.serif'] = ['Times New Roman']

have no effect, I get the same error as above. The true type fonts directory:

path_to_miniconda/miniconda3/envs/conda34/lib/python3.4/site-packages/matplotlib/mpl-data/fonts/ttf/

only has 40 fonts in it of the type: DejaVuSerif,DejaVuSans,STIX,cmb, cmt, cmy

Any idea what could be going on and how I can add additional fonts? Thanks!

Answer 1

To get it to work, I had to combine the two current top answers. Here's what worked for me:

$ sudo apt install msttcorefonts -qq
$ rm ~/.cache/matplotlib -rf