我无法使用Matplotlib将其以pdf格式保存

Question

I work in a project that uses MatplotLib for plotting and saving simple graphics. But since last update of Windows, if I use text in Latex format, I can not save a picture in pdf format. See below a trial of plotting in Spyder:

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()

This code generate the follow error:

Traceback (most recent call last):

  File "<ipython-input-25-375950fa7d9a>", line 1, in <module>
    runfile('C:/Users/Fábio/Desktop/plotter.py', wdir='C:/Users/Fábio/Desktop')

  File "C:\ProgramData\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 705, in runfile
    execfile(filename, namespace)

  File "C:\ProgramData\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 102, in execfile
    exec(compile(f.read(), filename, 'exec'), namespace)

  File "C:/Users/Fábio/Desktop/plotter.py", line 15, in <module>
    plt.savefig('plot.pdf', bbox_inches='tight')

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\pyplot.py", line 701, in savefig
    res = fig.savefig(*args, **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\figure.py", line 1834, in savefig
    self.canvas.print_figure(fname, **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\backend_bases.py", line 2216, in print_figure
    **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\backends\backend_pdf.py", line 2592, in print_pdf
    self.figure.draw(renderer)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\artist.py", line 55, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\figure.py", line 1299, in draw
    renderer, self, artists, self.suppressComposite)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\image.py", line 138, in _draw_list_compositing_images
    a.draw(renderer)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\artist.py", line 55, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\axes\_base.py", line 2437, in draw
    mimage._draw_list_compositing_images(renderer, self, artists)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\image.py", line 138, in _draw_list_compositing_images
    a.draw(renderer)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\artist.py", line 55, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\axis.py", line 1138, in draw
    tick.draw(renderer)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\artist.py", line 55, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\axis.py", line 282, in draw
    self.label1.draw(renderer)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\artist.py", line 55, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\text.py", line 762, in draw
    mtext=mtext)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\backends\backend_pdf.py", line 1944, in draw_tex
    pdfname = self.file.dviFontName(dvifont)

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\backends\backend_pdf.py", line 688, in dviFontName
    psfont = self.texFontMap[dvifont.texname]

  File "C:\ProgramData\Anaconda3\lib\site-packages\matplotlib\backends\backend_pdf.py", line 673, in texFontMap
    dviread.find_tex_file('pdftex.map'))

  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)

The code above work without any problem for save in different formats (.png and .eps, eg) but crash with .pdf. Before the update of Windows and using tha same configuration for Latex and Python, this save function work perfect for save in .pdf.

So I ask that you help me solve this problem, if possible.

Ps.: The code as exemple was tested in Spyder 3.2.6 with Python 3.6.4. The Latex workspace used contains the basics packages from Miktex and work perfectly for save the doc in .pdf or transform a .png / .eps figure in .pdf

Without further ado, I thank you immensely for your attention.

Answer 1

This most likely occurs due to your Windows user name folder containing country specific characters (á).

The return result.decode('ascii') cannot decode this and will not generate a valid path to your .tfm-files , which contains all the information needed by matlibplot to generate the latex font.

By changing the divread.py file in the matlibplot library to result.decode('utf-8') , the problem should be fixed. I do not know if this breaks any other dependencies, but it works well for me.