Latex error when using matplotlib with usetex=True

Bug description

When using matplotlib with usetex=True, a Latex error is produced.

Actual behaviour

The example below produces

---------------------------------------------------------------------------
CalledProcessError                        Traceback (most recent call last)
/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/texmanager.py in _run_checked_subprocess(self, command, tex)
    304                                              cwd=self.texcache,
--> 305                                              stderr=subprocess.STDOUT)
    306         except FileNotFoundError as exc:

/srv/conda/envs/notebook/lib/python3.7/subprocess.py in check_output(timeout, *popenargs, **kwargs)
    410     return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
--> 411                **kwargs).stdout
    412 

/srv/conda/envs/notebook/lib/python3.7/subprocess.py in run(input, capture_output, timeout, check, *popenargs, **kwargs)
    511             raise CalledProcessError(retcode, process.args,
--> 512                                      output=stdout, stderr=stderr)
    513     return CompletedProcess(process.args, retcode, stdout, stderr)

CalledProcessError: Command '['latex', '-interaction=nonstopmode', '--halt-on-error', '/home/jovyan/.cache/matplotlib/tex.cache/1acea6f6c115d0ec7a634ed0529287b9.tex']' returned non-zero exit status 1.

The above exception was the direct cause of the following exception:

RuntimeError                              Traceback (most recent call last)
/srv/conda/envs/notebook/lib/python3.7/site-packages/IPython/core/formatters.py in __call__(self, obj)
    339                 pass
    340             else:
--> 341                 return printer(obj)
    342             # Finally look for special method names
    343             method = get_real_method(obj, self.print_method)

/srv/conda/envs/notebook/lib/python3.7/site-packages/IPython/core/pylabtools.py in <lambda>(fig)
    246 
    247     if 'png' in formats:
--> 248         png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png', **kwargs))
    249     if 'retina' in formats or 'png2x' in formats:
    250         png_formatter.for_type(Figure, lambda fig: retina_figure(fig, **kwargs))

/srv/conda/envs/notebook/lib/python3.7/site-packages/IPython/core/pylabtools.py in print_figure(fig, fmt, bbox_inches, **kwargs)
    130         FigureCanvasBase(fig)
    131 
--> 132     fig.canvas.print_figure(bytes_io, **kw)
    133     data = bytes_io.getvalue()
    134     if fmt == 'svg':

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/backend_bases.py in print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, bbox_inches, **kwargs)
   2077                             print_method, dpi=dpi, orientation=orientation),
   2078                         draw_disabled=True)
-> 2079                     self.figure.draw(renderer)
   2080                     bbox_artists = kwargs.pop("bbox_extra_artists", None)
   2081                     bbox_inches = self.figure.get_tightbbox(renderer,

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     36                 renderer.start_filter()
     37 
---> 38             return draw(artist, renderer, *args, **kwargs)
     39         finally:
     40             if artist.get_agg_filter() is not None:

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/figure.py in draw(self, renderer)
   1734             self.patch.draw(renderer)
   1735             mimage._draw_list_compositing_images(
-> 1736                 renderer, self, artists, self.suppressComposite)
   1737 
   1738             renderer.close_group('figure')

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    135     if not_composite or not has_images:
    136         for a in artists:
--> 137             a.draw(renderer)
    138     else:
    139         # Composite any adjacent images together

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     36                 renderer.start_filter()
     37 
---> 38             return draw(artist, renderer, *args, **kwargs)
     39         finally:
     40             if artist.get_agg_filter() is not None:

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/axes/_base.py in draw(self, renderer, inframe)
   2628             renderer.stop_rasterizing()
   2629 
-> 2630         mimage._draw_list_compositing_images(renderer, self, artists)
   2631 
   2632         renderer.close_group('axes')

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    135     if not_composite or not has_images:
    136         for a in artists:
--> 137             a.draw(renderer)
    138     else:
    139         # Composite any adjacent images together

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     36                 renderer.start_filter()
     37 
---> 38             return draw(artist, renderer, *args, **kwargs)
     39         finally:
     40             if artist.get_agg_filter() is not None:

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/axis.py in draw(self, renderer, *args, **kwargs)
   1227         ticks_to_draw = self._update_ticks()
   1228         ticklabelBoxes, ticklabelBoxes2 = self._get_tick_bboxes(ticks_to_draw,
-> 1229                                                                 renderer)
   1230 
   1231         for tick in ticks_to_draw:

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/axis.py in _get_tick_bboxes(self, ticks, renderer)
   1172         """Return lists of bboxes for ticks' label1's and label2's."""
   1173         return ([tick.label1.get_window_extent(renderer)
-> 1174                  for tick in ticks if tick.label1.get_visible()],
   1175                 [tick.label2.get_window_extent(renderer)
   1176                  for tick in ticks if tick.label2.get_visible()])

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/axis.py in <listcomp>(.0)
   1172         """Return lists of bboxes for ticks' label1's and label2's."""
   1173         return ([tick.label1.get_window_extent(renderer)
-> 1174                  for tick in ticks if tick.label1.get_visible()],
   1175                 [tick.label2.get_window_extent(renderer)
   1176                  for tick in ticks if tick.label2.get_visible()])

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/text.py in get_window_extent(self, renderer, dpi)
    903             raise RuntimeError('Cannot get window extent w/o renderer')
    904 
--> 905         bbox, info, descent = self._get_layout(self._renderer)
    906         x, y = self.get_unitless_position()
    907         x, y = self.get_transform().transform((x, y))

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/text.py in _get_layout(self, renderer)
    291         _, lp_h, lp_d = renderer.get_text_width_height_descent(
    292             "lp", self._fontproperties,
--> 293             ismath="TeX" if self.get_usetex() else False)
    294         min_dy = (lp_h - lp_d) * self._linespacing
    295 

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/backends/backend_agg.py in get_text_width_height_descent(self, s, prop, ismath)
    202             fontsize = prop.get_size_in_points()
    203             w, h, d = texmanager.get_text_width_height_descent(
--> 204                 s, fontsize, renderer=self)
    205             return w, h, d
    206 

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/texmanager.py in get_text_width_height_descent(self, tex, fontsize, renderer)
    448         else:
    449             # use dviread. It sometimes returns a wrong descent.
--> 450             dvifile = self.make_dvi(tex, fontsize)
    451             with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:
    452                 page, = dvi

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/texmanager.py in make_dvi(self, tex, fontsize)
    337                 self._run_checked_subprocess(
    338                     ["latex", "-interaction=nonstopmode", "--halt-on-error",
--> 339                      texfile], tex)
    340             for fname in glob.glob(basefile + '*'):
    341                 if not fname.endswith(('dvi', 'tex')):

/srv/conda/envs/notebook/lib/python3.7/site-packages/matplotlib/texmanager.py in _run_checked_subprocess(self, command, tex)
    316                     prog=command[0],
    317                     tex=tex.encode('unicode_escape'),
--> 318                     exc=exc.output.decode('utf-8'))) from exc
    319         _log.debug(report)
    320         return report

RuntimeError: latex was not able to process the following string:
b'lp'

Here is the full report generated by latex:
This is pdfTeX, Version 3.14159265-2.6-1.40.18 (TeX Live 2017/Debian) (preloaded format=latex)
 restricted \write18 enabled.
entering extended mode
(/home/jovyan/.cache/matplotlib/tex.cache/1acea6f6c115d0ec7a634ed0529287b9.tex
LaTeX2e <2017-04-15>
Babel <3.18> and hyphenation patterns for 7 language(s) loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/usr/share/texlive/texmf-dist/tex/latex/base/size10.clo))
(/usr/share/texlive/texmf-dist/tex/latex/type1cm/type1cm.sty)

! LaTeX Error: File `type1ec.sty' not found.

Type X to quit or <RETURN> to proceed,
or enter new name. (Default extension: sty)

Enter file name: 
! Emergency stop.
<read *> 
         
l.5 \usepackage
               {type1ec}^^M
No pages of output.
Transcript written on 1acea6f6c115d0ec7a634ed0529287b9.log.

How to reproduce

1. Open an arbitrary Binder notebook with Python 3 kernel
2. Paste the following

import matplotlib.pyplot as plt
plt.rc('text', usetex=True)
fig = plt.figure()
ax = fig.add_subplot()

1. Execute
2. See error

[matqr]

I kept experiencing the same problem and after reading a bit more, I think the issue is regarding the installed version of LaTeX. I solved the problem by installing the cm-super family (e.g., sudo apt install cm-super)

[berndflemisch]

Ok, thanks for pointing me there. In fact, the issue tracker there tells me that I should file an issue at https://github.com/jupyterhub/binder/issues. Which I did: https://github.com/jupyterhub/binder/issues/211.