Unicode troubleshooting when trying to save a picture with latex text in Matplotlib

Question

Talk personal. I have a problem using the Matplotlib library. Before the last Windows update I used the library without any problem. I basically use it to create function charts and save them on. pdf using Latex formatting for the text, below follows a code as an example:

import numpy as np
from matplotlib import pyplot as plt

# Data for plot
step = 0.001
x = np.arange(0, 2 + step, step)
y = x*x*np.cos(10*x)

plt.rc('text', usetex=True)
 plt.rc('font', family='serif')
plt.figure(figsize=(19.2, 10.8))

plt.plot(x, y, lw=2)
plt.title(r'Function $f(x) = x^2 \cos(10x)$')
plt.savefig('plot.pdf', bbox_inches='tight')
plt.show()
plt.close()

However after the update my old windows bugged and I was forced to format the pc, and now I can’t use the same code above and save the figures in . pdf, the following error happens:

File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\dviread.py", line 1057, in find_tex_file
 return result.decode('ascii')

UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 10: ordinal not in range(128)

Using the same code I am able to save in other formats, for example . png and .eps. After formatting I basically installed the same software I used before.

Ps. The above code has been tested on Spyder 3.2.6 and Pycharm 2018.1.3 with Python version 3.6.4. Latex is working perfectly. I use Miktex for Latex base and Texstudio editor.

Answer 1

Probably the plot.pdf contains accents, maybe setting yourself at the top of the document:

# -*- coding: utf-8 -*-

import numpy as np
from matplotlib import pyplot as plt
...

If you are running via cmd run before running your script:

chcp 65001

---

As the example in https://matplotlib.org/examples/text_labels_and_annotations/unicode_demo.html

For utf-8 you may have to add as well:

from __future__ import unicode_literals

Should stay like this:

# -*- coding: utf-8 -*-

from __future__ import unicode_literals

import numpy as np

from matplotlib import pyplot as plt
...

Answer 2

So after a lot of suffering I managed to solve the problem.

To use latex, the matplotlib library uses the log path to access the Miktex workplace. It turns out that the username I was using was Fabio, with the accent. Then when the library tried to access the path it found a path, which when used to export the figure, resulted in the Unicodedecorror.

So I created another Fabio user, deleted the old one and reinstalled Miktex. After that the error ceased.