René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"creating PathCollection proxy artist with %matplotlib inline raises ValueError: cannot convert float NaN to integer","articleBody":"First, I'm not sure if this is a `matplotlib`or a `jupyter` bug, so I apologize if I'm posting at the wrong place.\r\n\r\nI'm having some problems with some code that used to work in a previous version of maptlotlib+jupyter notebook.\r\nI managed to trace the problem to creating an empty PathCollection to be used as a legend proxy artist, but the Exception is only raised when using the `inline` backend (`%matplotlib inline`). The code works fine using `%matplotlib notebook` or in ipython using the `MacOSX` backend\r\n\r\n### Bug report\r\n\r\n**Bug summary**\r\n\r\n\u003c!--A short 1-2 sentences that succinctly describes the bug--\u003e\r\n\r\n**Code for reproduction**\r\n\r\n\u003c!--A minimum code snippet required to reproduce the bug, also minimizing the number of dependencies required--\u003e\r\n\r\n```python\r\n%matplotlib inline\r\nfrom matplotlib import pyplot as plt\r\n_, ax = plt.subplots()\r\na = ax.scatter([], [], clip_on=False,\r\n                 marker='s', s=20, facecolor='k', \r\n                 edgecolors='r', linewidths=5, \r\n                 zorder=100, label='label')\r\nax.legend(handles=[a])\r\n\r\nplt.show()\r\n```\r\n\r\n**Actual outcome**\r\n\r\n\u003c!--The output produced by the above code, which may be a screenshot, console output, etc.--\u003e\r\n\r\n```\r\nValueError                                Traceback (most recent call last)\r\n~/anaconda3/lib/python3.6/site-packages/IPython/core/formatters.py in __call__(self, obj)\r\n    339                 pass\r\n    340             else:\r\n--\u003e 341                 return printer(obj)\r\n    342             # Finally look for special method names\r\n    343             method = get_real_method(obj, self.print_method)\r\n\r\n~/anaconda3/lib/python3.6/site-packages/IPython/core/pylabtools.py in \u003clambda\u003e(fig)\r\n    236 \r\n    237     if 'png' in formats:\r\n--\u003e 238         png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png', **kwargs))\r\n    239     if 'retina' in formats or 'png2x' in formats:\r\n    240         png_formatter.for_type(Figure, lambda fig: retina_figure(fig, **kwargs))\r\n\r\n~/anaconda3/lib/python3.6/site-packages/IPython/core/pylabtools.py in print_figure(fig, fmt, bbox_inches, **kwargs)\r\n    120 \r\n    121     bytes_io = BytesIO()\r\n--\u003e 122     fig.canvas.print_figure(bytes_io, **kw)\r\n    123     data = bytes_io.getvalue()\r\n    124     if fmt == 'svg':\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/backend_bases.py in print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, **kwargs)\r\n   2265                 orientation=orientation,\r\n   2266                 bbox_inches_restore=_bbox_inches_restore,\r\n-\u003e 2267                 **kwargs)\r\n   2268         finally:\r\n   2269             if bbox_inches and restore_bbox:\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/backends/backend_agg.py in print_png(self, filename_or_obj, *args, **kwargs)\r\n    505 \r\n    506     def print_png(self, filename_or_obj, *args, **kwargs):\r\n--\u003e 507         FigureCanvasAgg.draw(self)\r\n    508         renderer = self.get_renderer()\r\n    509         original_dpi = renderer.dpi\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/backends/backend_agg.py in draw(self)\r\n    428             # if toolbar:\r\n    429             #     toolbar.set_cursor(cursors.WAIT)\r\n--\u003e 430             self.figure.draw(self.renderer)\r\n    431         finally:\r\n    432             # if toolbar:\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)\r\n     53                 renderer.start_filter()\r\n     54 \r\n---\u003e 55             return draw(artist, renderer, *args, **kwargs)\r\n     56         finally:\r\n     57             if artist.get_agg_filter() is not None:\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/figure.py in draw(self, renderer)\r\n   1297 \r\n   1298             mimage._draw_list_compositing_images(\r\n-\u003e 1299                 renderer, self, artists, self.suppressComposite)\r\n   1300 \r\n   1301             renderer.close_group('figure')\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)\r\n    136     if not_composite or not has_images:\r\n    137         for a in artists:\r\n--\u003e 138             a.draw(renderer)\r\n    139     else:\r\n    140         # Composite any adjacent images together\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)\r\n     53                 renderer.start_filter()\r\n     54 \r\n---\u003e 55             return draw(artist, renderer, *args, **kwargs)\r\n     56         finally:\r\n     57             if artist.get_agg_filter() is not None:\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/axes/_base.py in draw(self, renderer, inframe)\r\n   2435             renderer.stop_rasterizing()\r\n   2436 \r\n-\u003e 2437         mimage._draw_list_compositing_images(renderer, self, artists)\r\n   2438 \r\n   2439         renderer.close_group('axes')\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)\r\n    136     if not_composite or not has_images:\r\n    137         for a in artists:\r\n--\u003e 138             a.draw(renderer)\r\n    139     else:\r\n    140         # Composite any adjacent images together\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)\r\n     53                 renderer.start_filter()\r\n     54 \r\n---\u003e 55             return draw(artist, renderer, *args, **kwargs)\r\n     56         finally:\r\n     57             if artist.get_agg_filter() is not None:\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/axis.py in draw(self, renderer, *args, **kwargs)\r\n   1131         renderer.open_group(__name__)\r\n   1132 \r\n-\u003e 1133         ticks_to_draw = self._update_ticks(renderer)\r\n   1134         ticklabelBoxes, ticklabelBoxes2 = self._get_tick_bboxes(ticks_to_draw,\r\n   1135                                                                 renderer)\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/axis.py in _update_ticks(self, renderer)\r\n    972 \r\n    973         interval = self.get_view_interval()\r\n--\u003e 974         tick_tups = list(self.iter_ticks())\r\n    975         if self._smart_bounds and tick_tups:\r\n    976             # handle inverted limits\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/axis.py in iter_ticks(self)\r\n    915         Iterate through all of the major and minor ticks.\r\n    916         \"\"\"\r\n--\u003e 917         majorLocs = self.major.locator()\r\n    918         majorTicks = self.get_major_ticks(len(majorLocs))\r\n    919         self.major.formatter.set_locs(majorLocs)\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/ticker.py in __call__(self)\r\n   1951     def __call__(self):\r\n   1952         vmin, vmax = self.axis.get_view_interval()\r\n-\u003e 1953         return self.tick_values(vmin, vmax)\r\n   1954 \r\n   1955     def tick_values(self, vmin, vmax):\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/ticker.py in tick_values(self, vmin, vmax)\r\n   1959         vmin, vmax = mtransforms.nonsingular(\r\n   1960             vmin, vmax, expander=1e-13, tiny=1e-14)\r\n-\u003e 1961         locs = self._raw_ticks(vmin, vmax)\r\n   1962 \r\n   1963         prune = self._prune\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/ticker.py in _raw_ticks(self, vmin, vmax)\r\n   1901         if self._nbins == 'auto':\r\n   1902             if self.axis is not None:\r\n-\u003e 1903                 nbins = np.clip(self.axis.get_tick_space(),\r\n   1904                                 max(1, self._min_n_ticks - 1), 9)\r\n   1905             else:\r\n\r\n~/anaconda3/lib/python3.6/site-packages/matplotlib/axis.py in get_tick_space(self)\r\n   2060         size = tick.label1.get_size() * 3\r\n   2061         if size \u003e 0:\r\n-\u003e 2062             return int(np.floor(length / size))\r\n   2063         else:\r\n   2064             return 2**31 - 1\r\n\r\nValueError: cannot convert float NaN to integer\r\n```\r\n\r\n**Expected outcome**\r\n\r\nThe exact same code using %matplotlib notebook\r\n```python\r\n%matplotlib notebook\r\nfrom matplotlib import pyplot as plt\r\n_, ax = plt.subplots()\r\na = ax.scatter([], [], clip_on=False,\r\n                 marker='s', s=20, facecolor='k', \r\n                 edgecolors='r', linewidths=5, \r\n                 zorder=100, label='label')\r\nax.legend(handles=[a])\r\n\r\nplt.show()\r\n```\r\nproduces the expected output\r\n![download](https://user-images.githubusercontent.com/13396853/35683348-ef976316-0763-11e8-8b2d-2d9a8bf32cfd.png)\r\n\r\nThe code using %matplotlib inline used to work before, but unfortunately, I don't know which version of matplotlib/jupyter I was using\r\n\r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system: OSX\r\n  * Matplotlib version: 2.1.2\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): module://ipykernel.pylab.backend_inline\r\n  * Python version: Python 3.6.4 |Anaconda custom (64-bit)\r\n  * Jupyter version (if applicable): `The version of the notebook server is: 5.3.1`\r\n  * Other libraries: \r\n\r\n\u003c!--Please tell us how you installed matplotlib and python e.g., from source, pip, conda--\u003e\r\n\u003c!--If you installed from conda, please specify which channel you used if not the default--\u003e\r\n\r\n","author":{"url":"https://github.com/DizietAsahi","@type":"Person","name":"DizietAsahi"},"datePublished":"2018-02-01T14:27:36.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":7},"url":"https://github.com/10360/matplotlib/issues/10360"}