RuntimeError: Failed to process string with tex because latex could not be found

Question

I was trying to render text with LaTeX in Matplotlib. There is a demo provided by Matplotlib at https://matplotlib.org/3.1.1/gallery/text_labels_and_annotations/tex_demo.html.

However, when I ran this demo, I got this error saying "RuntimeError: Failed to process string with tex because latex could not be found", but I'm sure I have installed Miktex and Ghostscript required by Matlibplot.

Anyone knows how should I solve it? Thanks.

import numpy as np
import matplotlib
matplotlib.rcParams['text.usetex'] = True
import matplotlib.pyplot as plt


t = np.linspace(0.0, 1.0, 100)
s = np.cos(4 * np.pi * t) + 2

fig, ax = plt.subplots(figsize=(6, 4), tight_layout=True)
ax.plot(t, s)

ax.set_xlabel(r'\textbf{time (s)}')
ax.set_ylabel('\\textit{Velocity (\N{DEGREE SIGN}/sec)}', fontsize=16)
ax.set_title(r'\TeX\ is Number $\displaystyle\sum_{n=1}^\infty'
             r'\frac{-e^{i\pi}}{2^n}$!', fontsize=16, color='r')
plt.show()

Here is the error trace back:

Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 304, in _run_checked_subprocess
    stderr=subprocess.STDOUT)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 336, in check_output
    **kwargs).stdout
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 403, in run
    with Popen(*popenargs, **kwargs) as process:
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 997, in _execute_child
    startupinfo)
FileNotFoundError: [WinError 2] The System Cannot Find the File Specified
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\tkinter\__init__.py", line 1702, in __call__
    return self.func(*args)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\tkinter\__init__.py", line 746, in callit
    func(*args)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\_backend_tk.py", line 338, in idle_draw
    self.draw()
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_tkagg.py", line 9, in draw
    super(FigureCanvasTkAgg, self).draw()
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_agg.py", line 388, in draw
    self.figure.draw(self.renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\artist.py", line 38, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\figure.py", line 1702, in draw
    **self._tight_parameters)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\figure.py", line 2476, in tight_layout
    pad=pad, h_pad=h_pad, w_pad=w_pad, rect=rect)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 362, in get_tight_layout_figure
    pad=pad, h_pad=h_pad, w_pad=w_pad)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 111, in auto_adjust_subplotpars
    tight_bbox_raw = union([ax.get_tightbbox(renderer) for ax in subplots
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 112, in <listcomp>
    if ax.get_visible()])
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axes\_base.py", line 4355, in get_tightbbox
    bb_xaxis = self.xaxis.get_tightbbox(renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1164, in get_tightbbox
    self._update_label_position(renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 2014, in _update_label_position
    bboxes, bboxes2 = self._get_tick_boxes_siblings(renderer=renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1999, in _get_tick_boxes_siblings
    tlb, tlb2 = axx.xaxis._get_tick_bboxes(ticks_to_draw, renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1150, in _get_tick_bboxes
    for tick in ticks if tick.label1.get_visible()],
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1150, in <listcomp>
    for tick in ticks if tick.label1.get_visible()],
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\text.py", line 890, in get_window_extent
    bbox, info, descent = self._get_layout(self._renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\text.py", line 291, in _get_layout
    ismath="TeX" if self.get_usetex() else False)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_agg.py", line 201, in get_text_width_height_descent
    s, fontsize, renderer=self)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 448, in get_text_width_height_descent
    dvifile = self.make_dvi(tex, fontsize)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 338, in make_dvi
    texfile], tex)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\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
Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 304, in _run_checked_subprocess
    stderr=subprocess.STDOUT)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 336, in check_output
    **kwargs).stdout
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 403, in run
    with Popen(*popenargs, **kwargs) as process:
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 997, in _execute_child
    startupinfo)
FileNotFoundError: [WinError 2] The System Cannot Find the File Specified
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\tkinter\__init__.py", line 1702, in __call__
    return self.func(*args)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\_backend_tk.py", line 259, in resize
    self.draw()
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_tkagg.py", line 9, in draw
    super(FigureCanvasTkAgg, self).draw()
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_agg.py", line 388, in draw
    self.figure.draw(self.renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\artist.py", line 38, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\figure.py", line 1702, in draw
    **self._tight_parameters)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\figure.py", line 2476, in tight_layout
    pad=pad, h_pad=h_pad, w_pad=w_pad, rect=rect)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 362, in get_tight_layout_figure
    pad=pad, h_pad=h_pad, w_pad=w_pad)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 111, in auto_adjust_subplotpars
    tight_bbox_raw = union([ax.get_tightbbox(renderer) for ax in subplots
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 112, in <listcomp>
    if ax.get_visible()])
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axes\_base.py", line 4355, in get_tightbbox
    bb_xaxis = self.xaxis.get_tightbbox(renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1164, in get_tightbbox
    self._update_label_position(renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 2014, in _update_label_position
    bboxes, bboxes2 = self._get_tick_boxes_siblings(renderer=renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1999, in _get_tick_boxes_siblings
    tlb, tlb2 = axx.xaxis._get_tick_bboxes(ticks_to_draw, renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1150, in _get_tick_bboxes
    for tick in ticks if tick.label1.get_visible()],
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1150, in <listcomp>
    for tick in ticks if tick.label1.get_visible()],
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\text.py", line 890, in get_window_extent
    bbox, info, descent = self._get_layout(self._renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\text.py", line 291, in _get_layout
    ismath="TeX" if self.get_usetex() else False)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_agg.py", line 201, in get_text_width_height_descent
    s, fontsize, renderer=self)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 448, in get_text_width_height_descent
    dvifile = self.make_dvi(tex, fontsize)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 338, in make_dvi
    texfile], tex)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\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
Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 304, in _run_checked_subprocess
    stderr=subprocess.STDOUT)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 336, in check_output
    **kwargs).stdout
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 403, in run
    with Popen(*popenargs, **kwargs) as process:
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\subprocess.py", line 997, in _execute_child
    startupinfo)
FileNotFoundError: [WinError 2] The System Cannot Find the File Specified

Traceback (most recent call last):
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\tkinter\__init__.py", line 1702, in __call__
    return self.func(*args)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\tkinter\__init__.py", line 746, in callit
    func(*args)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\_backend_tk.py", line 338, in idle_draw
    self.draw()
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_tkagg.py", line 9, in draw
    super(FigureCanvasTkAgg, self).draw()
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_agg.py", line 388, in draw
    self.figure.draw(self.renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\artist.py", line 38, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\figure.py", line 1702, in draw
    **self._tight_parameters)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\figure.py", line 2476, in tight_layout
    pad=pad, h_pad=h_pad, w_pad=w_pad, rect=rect)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 362, in get_tight_layout_figure
    pad=pad, h_pad=h_pad, w_pad=w_pad)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 111, in auto_adjust_subplotpars
    tight_bbox_raw = union([ax.get_tightbbox(renderer) for ax in subplots
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\tight_layout.py", line 112, in <listcomp>
    if ax.get_visible()])
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axes\_base.py", line 4355, in get_tightbbox
    bb_xaxis = self.xaxis.get_tightbbox(renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1164, in get_tightbbox
    self._update_label_position(renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 2014, in _update_label_position
    bboxes, bboxes2 = self._get_tick_boxes_siblings(renderer=renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1999, in _get_tick_boxes_siblings
    tlb, tlb2 = axx.xaxis._get_tick_bboxes(ticks_to_draw, renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1150, in _get_tick_bboxes
    for tick in ticks if tick.label1.get_visible()],
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\axis.py", line 1150, in <listcomp>
    for tick in ticks if tick.label1.get_visible()],
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\text.py", line 890, in get_window_extent
    bbox, info, descent = self._get_layout(self._renderer)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\text.py", line 291, in _get_layout
    ismath="TeX" if self.get_usetex() else False)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\backends\backend_agg.py", line 201, in get_text_width_height_descent
    s, fontsize, renderer=self)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 448, in get_text_width_height_descent
    dvifile = self.make_dvi(tex, fontsize)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\lib\site-packages\matplotlib\texmanager.py", line 338, in make_dvi
    texfile], tex)
  File "C:\Users\haiqing\Anaconda3\envs\mie324\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

According to the matplotlib documentation:

Matplotlib's LaTeX support requires a working LaTeX installation, dvipng (which may be included with your LaTeX installation), and Ghostscript (GPL Ghostscript 9.0 or later is required). The executables for these external dependencies must all be located on your PATH.

If you're not familiar with PATH, this means that the .exe files of these programs need to be in your system environment variables. In Windows, Edit the System Environment Variables, click on variable Path, and add the filepaths of the aforementioned programs to the list.

• Get LaTex here
• Get dvipng here
• Get Ghostscript > 9.0 here

Answer 2

I managed to solve this issue by installing texlive and latex. In apt based Linux, this command installs texlive:

sudo apt install texlive texlive-latex-extra texlive-fonts-recommended dvipng

latex can be easily installed via pip:

pip install latex

Answer 3

When I tried to change the standard font for matplotlib, I likely incorrectly applied a recommended script and broke my matplotlib and from that moment on always got this error message.

Simply resetting matplotlib settings worked perfectly for me.

import matplotlib as mpl
mpl.rcParams.update(mpl.rcParamsDefault)