basic_classification.ipynb plot error

[avehtari]

Using

The version of the notebook server is 4.1.0 and is running on:
Python 3.5.1 |Anaconda custom (64-bit)| (default, Dec 7 2015, 11:16:01)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-1)]
Current Kernel Information:
Python 3.5.1 |Anaconda custom (64-bit)| (default, Dec 7 2015, 11:16:01)
IPython 4.1.2 -- An enhanced Interactive Python.

plt.plot(X, f, 'bo') line in basic_classification.ipynb gives the error below

[<matplotlib.lines.Line2D at 0x7f1244069748>]

Error in callback <function install_repl_displayhook..post_execute at 0x7f124f6e2950> (for post_execute):

RuntimeError Traceback (most recent call last)
/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/pyplot.py in post_execute()
145 def post_execute():
146 if matplotlib.is_interactive():
--> 147 draw_all()
148
149 # IPython >= 2

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/_pylab_helpers.py in draw_all(cls, force)
148 for f_mgr in cls.get_all_fig_managers():
149 if force or f_mgr.canvas.figure.stale:
--> 150 f_mgr.canvas.draw_idle()
151
152 atexit.register(Gcf.destroy_all)

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/backend_bases.py in draw_idle(self, _args, *_kwargs)
2024 if not self._is_idle_drawing:
2025 with self._idle_draw_cntx():
-> 2026 self.draw(_args, *_kwargs)
2027
2028 def draw_cursor(self, event):

/home/ave/anaconda3/lib/python3.5/contextlib.py in exit(self, type, value, traceback)
75 value = type()
76 try:
---> 77 self.gen.throw(type, value, traceback)
78 raise RuntimeError("generator didn't stop after throw()")
79 except StopIteration as exc:

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/backend_bases.py in _idle_draw_cntx(self)
1698 def _idle_draw_cntx(self):
1699 self._is_idle_drawing = True
-> 1700 yield
1701 self._is_idle_drawing = False
1702

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/backend_bases.py in draw_idle(self, _args, *_kwargs)
2024 if not self._is_idle_drawing:
2025 with self._idle_draw_cntx():
-> 2026 self.draw(_args, *_kwargs)
2027
2028 def draw_cursor(self, event):

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/backends/backend_agg.py in draw(self)
472
473 try:
--> 474 self.figure.draw(self.renderer)
475 finally:
476 RendererAgg.lock.release()

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, _args, *_kwargs)
59 def draw_wrapper(artist, renderer, _args, *_kwargs):
60 before(artist, renderer)
---> 61 draw(artist, renderer, _args, *_kwargs)
62 after(artist, renderer)
63

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/figure.py in draw(self, renderer)
1157 dsu.sort(key=itemgetter(0))
1158 for zorder, a, func, args in dsu:
-> 1159 func(*args)
1160
1161 renderer.close_group('figure')

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, _args, *_kwargs)
59 def draw_wrapper(artist, renderer, _args, *_kwargs):
60 before(artist, renderer)
---> 61 draw(artist, renderer, _args, *_kwargs)
62 after(artist, renderer)
63

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/axes/_base.py in draw(self, renderer, inframe)
2322
2323 for zorder, a in dsu:
-> 2324 a.draw(renderer)
2325
2326 renderer.close_group('axes')

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, _args, *_kwargs)
59 def draw_wrapper(artist, renderer, _args, *_kwargs):
60 before(artist, renderer)
---> 61 draw(artist, renderer, _args, *_kwargs)
62 after(artist, renderer)
63

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/axis.py in draw(self, renderer, _args, *_kwargs)
1109
1110 for tick in ticks_to_draw:
-> 1111 tick.draw(renderer)
1112
1113 # scale up the axis label box to also find the neighbors, not

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, _args, *_kwargs)
59 def draw_wrapper(artist, renderer, _args, *_kwargs):
60 before(artist, renderer)
---> 61 draw(artist, renderer, _args, *_kwargs)
62 after(artist, renderer)
63

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/axis.py in draw(self, renderer)
250
251 if self.label1On:
--> 252 self.label1.draw(renderer)
253 if self.label2On:
254 self.label2.draw(renderer)

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, _args, *_kwargs)
59 def draw_wrapper(artist, renderer, _args, *_kwargs):
60 before(artist, renderer)
---> 61 draw(artist, renderer, _args, *_kwargs)
62 after(artist, renderer)
63

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/text.py in draw(self, renderer)
794 textrenderer.draw_text(gc, x, y, clean_line,
795 textobj._fontproperties, angle,
--> 796 ismath=ismath, mtext=mtext)
797
798 gc.restore()

/home/ave/anaconda3/lib/python3.5/contextlib.py in exit(self, type, value, traceback)
75 value = type()
76 try:
---> 77 self.gen.throw(type, value, traceback)
78 raise RuntimeError("generator didn't stop after throw()")
79 except StopIteration as exc:

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/text.py in _wrap_text(textobj)
58 textobj.set_text(old_text)
59 else:
---> 60 yield textobj
61
62

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/text.py in draw(self, renderer)
790 textrenderer.draw_tex(gc, x, y, clean_line,
791 textobj._fontproperties, angle,
--> 792 mtext=mtext)
793 else:
794 textrenderer.draw_text(gc, x, y, clean_line,

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/backends/backend_agg.py in draw_tex(self, gc, x, y, s, prop, angle, ismath, mtext)
251 texmanager = self.get_texmanager()
252
--> 253 Z = texmanager.get_grey(s, size, self.dpi)
254 Z = np.array(Z * 255.0, np.uint8)
255

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/texmanager.py in get_grey(self, tex, fontsize, dpi)
581
582 if alpha is None:
--> 583 pngfile = self.make_png(tex, fontsize, dpi)
584 X = read_png(os.path.join(self.texcache, pngfile))
585

/home/ave/anaconda3/lib/python3.5/site-packages/matplotlib/texmanager.py in make_png(self, tex, fontsize, dpi)
522 'dvipng was not able to process the following '
523 'file:\n%s\nHere is the full report generated by '
--> 524 'dvipng: \n\n' % dvifile + report)
525 else:
526 mpl.verbose.report(report, 'debug')

RuntimeError: dvipng was not able to process the following file:
/home/ave/.cache/matplotlib/tex.cache/c0175f5167fe83d1072385b1c5941a2d.dvi
Here is the full report generated by dvipng: