Unable to use latex in python plots - RuntimeError: LaTeX was not able to process the following string: b'lp' - matplotlib

Question

I want to use latex for the labels of a figure but I get the error
RuntimeError: LaTeX was not able to process the following string:
b'lp'
Here is the full report generated by LaTeX:
and that is it (I don't see any report)
Edit : Here is the whole error I obtain:
Traceback (most recent call last):
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_qt5agg.py", line 197, in __draw_idle_agg
FigureCanvasAgg.draw(self)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_agg.py", line 464, in draw
self.figure.draw(self.renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\artist.py", line 63, in draw_wrapper
draw(artist, renderer, *args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\figure.py", line 1144, in draw
renderer, self, dsu, self.suppressComposite)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\image.py", line 139, in _draw_list_compositing_images
a.draw(renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\artist.py", line 63, in draw_wrapper
draw(artist, renderer, *args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\axes\_base.py", line 2426, in draw
mimage._draw_list_compositing_images(renderer, self, dsu)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\image.py", line 139, in _draw_list_compositing_images
a.draw(renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\artist.py", line 63, in draw_wrapper
draw(artist, renderer, *args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\axis.py", line 1138, in draw
renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\axis.py", line 1078, in _get_tick_bboxes
extent = tick.label1.get_window_extent(renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\text.py", line 967, in get_window_extent
bbox, info, descent = self._get_layout(self._renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\text.py", line 353, in _get_layout
ismath=False)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_agg.py", line 230, in get_text_width_height_descent
renderer=self)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 676, in get_text_width_height_descent
dvifile = self.make_dvi(tex, fontsize)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 423, in make_dvi
report))
RuntimeError: LaTeX was not able to process the following string:
b'lp'
Here is the full report generated by LaTeX:
Here is my code:
import numpy as np
from matplotlib import rc
import matplotlib.pyplot as plt
plt.close('all')
rc('text', usetex = True)
mu = np.linspace(0,10,100)
eta = mu**2
fig, ax = plt.subplots()
ax.plot(mu,eta,label= r'$\eta (\mu)$')
ax.set_title('Test')
ax.legend()
I installed MiKTeX, added it to the environment variables according to https://docs.alfresco.com/4.2/tasks/fot-addpath.html.
I checked the packages of MiKTeX, where I found "miktex-dvipng-bin-x64-2.9" in the "\MiKTeX excecutables" category. I deduce I have a dvipng.
I dowloaded Ghostcript, which I also added to the environment variables.
I tried compiling a latex script to pdf using texworks, and it worked just fine, from what I deduce LaTeX is properly installed.
From https://matplotlib.org/1.4.1/users/usetex.html, this is all I was supposed to need...
I tried deleting my .matplotlib/tex.cache directory
I tried writting
import matplotlib as mpl
mpl.rcParams['text.usetex']=True
instead of
from matplotlib import rc
rc('text', usetex = True)
but it yielded the same result.
Swiching
rc('text', usetex = True)
to
rc('text', usetex = False)
prevents the error, but my labels are not written with latex...
After a lot of googling, I'm short with ideas.
Could anyone help me please?
My configuration is:
- Python 3.6 (I run my code in spyder)
- MiKTeX 2.9
- Ghostscript 9.50
- Windows 10
- Edit : matplotlib 2.0.2
Edit : upgrading to matplotlib 3.1.1, I get the following error:
Traceback (most recent call last):
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 304, in _run_checked_subprocess
stderr=subprocess.STDOUT)
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 336, in check_output
**kwargs).stdout
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 403, in run
with Popen(*popenargs, **kwargs) as process:
File "C:\Users\Vincent\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 209, in __init__
super(SubprocessPopen, self).__init__(*args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 707, in __init__
restore_signals, start_new_session)
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 992, in _execute_child
startupinfo)
FileNotFoundError: [WinError 2] Le fichier spécifié est introuvable
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_qt5.py", line 505, in _draw_idle
self.draw()
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_agg.py", line 388, in draw
self.figure.draw(self.renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\artist.py", line 38, in draw_wrapper
return draw(artist, renderer, *args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\figure.py", line 1709, in draw
renderer, self, artists, self.suppressComposite)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\image.py", line 135, in _draw_list_compositing_images
a.draw(renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\artist.py", line 38, in draw_wrapper
return draw(artist, renderer, *args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\axes\_base.py", line 2607, in draw
self._update_title_position(renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\axes\_base.py", line 2556, in _update_title_position
if title.get_window_extent(renderer).ymin < top:
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\text.py", line 890, in get_window_extent
bbox, info, descent = self._get_layout(self._renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\text.py", line 291, in _get_layout
ismath="TeX" if self.get_usetex() else False)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_agg.py", line 201, in get_text_width_height_descent
s, fontsize, renderer=self)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 448, in get_text_width_height_descent
dvifile = self.make_dvi(tex, fontsize)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 338, in make_dvi
texfile], tex)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 308, in _run_checked_subprocess
'found'.format(command[0])) from exc
RuntimeError: Failed to process string with tex because latex could not be found
Traceback (most recent call last):
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 304, in _run_checked_subprocess
stderr=subprocess.STDOUT)
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 336, in check_output
**kwargs).stdout
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 403, in run
with Popen(*popenargs, **kwargs) as process:
File "C:\Users\Vincent\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 209, in __init__
super(SubprocessPopen, self).__init__(*args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 707, in __init__
restore_signals, start_new_session)
File "C:\Users\Vincent\Anaconda3\lib\subprocess.py", line 992, in _execute_child
startupinfo)
FileNotFoundError: [WinError 2] Le fichier spécifié est introuvable
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_qt5.py", line 505, in _draw_idle
self.draw()
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_agg.py", line 388, in draw
self.figure.draw(self.renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\artist.py", line 38, in draw_wrapper
return draw(artist, renderer, *args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\figure.py", line 1709, in draw
renderer, self, artists, self.suppressComposite)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\image.py", line 135, in _draw_list_compositing_images
a.draw(renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\artist.py", line 38, in draw_wrapper
return draw(artist, renderer, *args, **kwargs)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\axes\_base.py", line 2607, in draw
self._update_title_position(renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\axes\_base.py", line 2556, in _update_title_position
if title.get_window_extent(renderer).ymin < top:
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\text.py", line 890, in get_window_extent
bbox, info, descent = self._get_layout(self._renderer)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\text.py", line 291, in _get_layout
ismath="TeX" if self.get_usetex() else False)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\backends\backend_agg.py", line 201, in get_text_width_height_descent
s, fontsize, renderer=self)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 448, in get_text_width_height_descent
dvifile = self.make_dvi(tex, fontsize)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 338, in make_dvi
texfile], tex)
File "C:\Users\Vincent\Anaconda3\lib\site-packages\matplotlib\texmanager.py", line 308, in _run_checked_subprocess
'found'.format(command[0])) from exc
RuntimeError: Failed to process string with tex because latex could not be found

Answer 1

For about the 5th time I unistalled and reinstalled MikTeX, and this time my problem is solved. When running my python script, three windows opened successively asking for packages installations. I attach to this answer screenshots of these three windows. After accepting to install these packages, my script worked just fine. Previously, when unistalling and reinstalling MikTeX, I already saw windows asking for installation and accepted the installations. I don't know why this time it worked whilst it didn't work before...
Anyway, my problem was solved uninstalling and reinstalling MiKTeX, running my script and accepting packages.
Window for installation of a file from type1cm
Window for installation of a file from iftex
Window for installation of a file from zhmetrics