RuntimeError: latex was not able to process the following string: '_auto' - python-2.7

Question

To whom will concern my question,
I met a problem to perform the python code built by LIGO team on the jupyter notebook. When I tried to perform the following simple code without the environment of the jupyter notebook, I can obtain the correct output and the attached figure.
+++++++++++++++++++++++++++++++++
from gwpy.timeseries import TimeSeries
from numpy import random
series = TimeSeries(random.random(1000), sample_rate=100, unit='m')
plot = series.plot()
plot.show()
+++++++++++++++++++++++++++
Generation of random plots
But when I applied the following similar python code in the jupyter notebook:
++++++++++++++++
`%matplotlib inline`
%config InlineBackend.figure_format = 'retina'
from gwpy.timeseries import TimeSeries
from numpy import random
series = TimeSeries(random.random(1000), sample_rate=100, unit='m')
plot = series.plot()
++++++++++++++++
I obtained the runtime error related to the latex.
Since I can get the correct output if I do not use the jupyter, I speculate that the problem is caused by the transformation of the plot to present on the notebook environment.
I tried to check the related runtime error related to latex and install the packages (e.g., dvipng, texlive-latex-extra & texlive-fonts-recommended) through Macports or re-install MacTeX in my machine, but the problem still exists.
Here comes the warning & error messages I obtained on the jupyter notebook.
RuntimeError Traceback (most recent call last)
/Users/lupin/Library/Python/2.7/lib/python/site-packages/IPython/core/formatters.pyc in __call__(self, obj)
332 pass
333 else:
--> 334 return printer(obj)
335 # Finally look for special method names
336 method = get_real_method(obj, self.print_method)
/Users/lupin/Library/Python/2.7/lib/python/site-packages/IPython/core/pylabtools.pyc in <lambda>(fig)
247 png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png', **kwargs))
248 if 'retina' in formats or 'png2x' in formats:
--> 249 png_formatter.for_type(Figure, lambda fig: retina_figure(fig, **kwargs))
250 if 'jpg' in formats or 'jpeg' in formats:
251 jpg_formatter.for_type(Figure, lambda fig: print_figure(fig, 'jpg', **kwargs))
/Users/lupin/Library/Python/2.7/lib/python/site-packages/IPython/core/pylabtools.pyc in retina_figure(fig, **kwargs)
137 def retina_figure(fig, **kwargs):
138 """format a figure as a pixel-doubled (retina) PNG"""
--> 139 pngdata = print_figure(fig, fmt='retina', **kwargs)
140 # Make sure that retina_figure acts just like print_figure and returns
141 # None when the figure is empty.
/Users/lupin/Library/Python/2.7/lib/python/site-packages/IPython/core/pylabtools.pyc in print_figure(fig, fmt, bbox_inches, **kwargs)
129
130 bytes_io = BytesIO()
--> 131 fig.canvas.print_figure(bytes_io, **kw)
132 data = bytes_io.getvalue()
133 if fmt == 'svg':
/Library/Python/2.7/site-packages/matplotlib/backend_bases.pyc in print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, **kwargs)
2212 **kwargs)
2213 renderer = self.figure._cachedRenderer
-> 2214 bbox_inches = self.figure.get_tightbbox(renderer)
2215
2216 bbox_artists = kwargs.pop("bbox_extra_artists", None)
/Library/Python/2.7/site-packages/matplotlib/figure.pyc in get_tightbbox(self, renderer)
2188 for ax in self.axes:
2189 if ax.get_visible():
-> 2190 bb.append(ax.get_tightbbox(renderer))
2191
2192 if len(bb) == 0:
/Library/Python/2.7/site-packages/matplotlib/axes/_base.pyc in get_tightbbox(self, renderer, call_axes_locator)
4168 bb.append(self._right_title.get_window_extent(renderer))
4169
-> 4170 bb_xaxis = self.xaxis.get_tightbbox(renderer)
4171 if bb_xaxis:
4172 bb.append(bb_xaxis)
/Library/Python/2.7/site-packages/matplotlib/axis.pyc in get_tightbbox(self, renderer)
1158 for a in [self.label, self.offsetText]:
1159 if a.get_visible():
-> 1160 bb.append(a.get_window_extent(renderer))
1161
1162 bb.extend(ticklabelBoxes)
/Library/Python/2.7/site-packages/matplotlib/text.pyc in get_window_extent(self, renderer, dpi)
920 raise RuntimeError('Cannot get window extent w/o renderer')
921
--> 922 bbox, info, descent = self._get_layout(self._renderer)
923 x, y = self.get_unitless_position()
924 x, y = self.get_transform().transform_point((x, y))
/Library/Python/2.7/site-packages/matplotlib/text.pyc in _get_layout(self, renderer)
307 w, h, d = renderer.get_text_width_height_descent(clean_line,
308
self._fontproperties,
--> 309 ismath=ismath)
310 else:
311 w, h, d = 0, 0, 0
/Library/Python/2.7/site-packages/matplotlib/backends/backend_agg.pyc in get_text_width_height_descent(self, s, prop, ismath)
230 fontsize = prop.get_size_in_points()
231 w, h, d = texmanager.get_text_width_height_descent(
--> 232 s, fontsize, renderer=self)
233 return w, h, d
234
/Library/Python/2.7/site-packages/matplotlib/texmanager.pyc in get_text_width_height_descent(self, tex, fontsize, renderer)
499 else:
500 # use dviread. It sometimes returns a wrong descent.
--> 501 dvifile = self.make_dvi(tex, fontsize)
502 with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:
503 page = next(iter(dvi))
/Library/Python/2.7/site-packages/matplotlib/texmanager.pyc in make_dvi(self, tex, fontsize)
363 self._run_checked_subprocess(
364 ["latex", "-interaction=nonstopmode", "--halt-on-error",
--> 365 texfile], tex)
366 for fname in glob.glob(basefile + '*'):
367 if not fname.endswith(('dvi', 'tex')):
/Library/Python/2.7/site-packages/matplotlib/texmanager.pyc in _run_checked_subprocess(self, command, tex)
342 prog=command[0],
343 tex=tex.encode('unicode_escape'),
--> 344 exc=exc.output.decode('utf-8')))
345 _log.debug(report)
346 return report
RuntimeError: latex was not able to process the following string:
'_auto'
Here is the full report generated by latex:
This is pdfTeX, Version 3.14159265-2.6-1.40.18 (TeX Live 2017/MacPorts 2017_4) (preloaded format=latex)
restricted \write18 enabled.
entering extended mode
(/Users/lupin/.matplotlib/tex.cache/1de80ee53f095837776b678f34112ba4.tex
LaTeX2e <2017-04-15>
Babel <3.10> and hyphenation patterns for 3 language(s) loaded.
(/opt/local/share/texmf-texlive/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/opt/local/share/texmf-texlive/tex/latex/base/size10.clo))
(/opt/local/share/texmf-texlive/tex/latex/type1cm/type1cm.sty)
(/opt/local/share/texmf-texlive/tex/latex/base/textcomp.sty
(/opt/local/share/texmf-texlive/tex/latex/base/ts1enc.def))
(/opt/local/share/texmf-texlive/tex/latex/geometry/geometry.sty
(/opt/local/share/texmf-texlive/tex/latex/graphics/keyval.sty)
(/opt/local/share/texmf-texlive/tex/generic/oberdiek/ifpdf.sty)
(/opt/local/share/texmf-texlive/tex/generic/oberdiek/ifvtex.sty)
(/opt/local/share/texmf-texlive/tex/generic/ifxetex/ifxetex.sty)
Package geometry Warning: Over-specification in `h'-direction.
`width' (5058.9pt) is ignored.
Package geometry Warning: Over-specification in `v'-direction.
`height' (5058.9pt) is ignored.
) (./1de80ee53f095837776b678f34112ba4.aux)
(/opt/local/share/texmf-texlive/tex/latex/base/ts1cmr.fd)
*geometry* driver: auto-detecting
*geometry* detected driver: dvips
! Missing $ inserted.
<inserted text>
$
l.13 \fontsize{20.000000}{25.000000}{\rmfamily _
auto}
No pages of output.
Transcript written on 1de80ee53f095837776b678f34112ba4.log.
Can anyone provide some suggestions to solve this issue?

Answer 1

The '_' legend in latex indicates subscript, translator can't identify it out of '$$', replacing '_auto' with '-auto' may help:)