KeyError on run-time

[wookayin]

The following KeyError might happen during the execution (e.g. sess.run()) of plot functions, where an exception is thrown outside:

KeyError: (1.0, 0.01, '0.010', 'black', 'center_baseline', 'left', -1142507319491788459, None, None, 100.0, <weakref at 0x7fadaec55db8; to 'RendererAgg' at 0x7fadaca0b198>, 1.2)

Detailed stacktrace (click to expand)

  File "$PREFIX/lib/python3.6/site-packages/tfplot/ops.py", line 80, in _render_image
    image = figure.to_array(fig)

  File "$PREFIX/lib/python3.6/site-packages/tfplot/figure.py", line 81, in to_array
    fig.canvas.draw()

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/backends/backend_agg.py", line 402, in draw
    self.figure.draw(self.renderer)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/artist.py", line 50, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/figure.py", line 1649, in draw
    renderer, self, artists, self.suppressComposite)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/image.py", line 138, in _draw_list_compositing_images
    a.draw(renderer)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/artist.py", line 50, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/axes/_base.py", line 2628, in draw
    mimage._draw_list_compositing_images(renderer, self, artists)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/image.py", line 138, in _draw_list_compositing_images
    a.draw(renderer)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/artist.py", line 50, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/axis.py", line 1187, in draw
    renderer)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/axis.py", line 1125, in _get_tick_bboxes
    extent = tick.label1.get_window_extent(renderer)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/text.py", line 930, in get_window_extent
    bbox, info, descent = self._get_layout(self._renderer)

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/text.py", line 430, in _get_layout
    self._cached[key] = ret

  File "$PREFIX/lib/python3.6/site-packages/matplotlib/cbook/__init__.py", line 623, in __setitem__
    del self[self._killkeys[0]]

I suspect this would be a multithread-related issue (matplotlib is not thread-safe). The only workaround I have at this point is to simply ignore the exception.