René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: AttributeError: 'NoneType' object has no attribute 'rowspan' with mpl \u003e=3.7","articleBody":"### Bug summary\n\nWith mpl \u003c3.7 this code works the code snippet below works but it is broken in 3.7.0 and 3.7.1. The odd thing is that if I move the colorbar to the last line or if I don't use pandas to the the `C` plotting it works just fine. I guess there is a bad interaction somewhere that is messing up with the subplots.\n\n### Code for reproduction\n\n```python\nimport matplotlib.pyplot as plt\r\nimport pandas as pd\r\n\r\nfig = plt.figure()\r\n\r\naxes = fig.subplot_mosaic(\r\n    \"\"\"\r\n    AB\r\n    CC\r\n    \"\"\"\r\n)\r\n\r\nx = [1, 2, 3]\r\ny = [1, 2, 3]\r\n\r\ncs0 = axes[\"A\"].scatter(x, y)\r\ncs1 = axes[\"B\"].scatter(x, y)\r\n\r\nfig.colorbar(cs0, ax=[axes[\"A\"], axes[\"B\"]], location=\"right\")\r\naxes[\"C\"].plot(x)\r\npd.DataFrame(x).plot(ax=axes[\"C\"])\n```\n\n\n### Actual outcome\n\n```\r\nAttributeError                            Traceback (most recent call last)\r\nCell In[10], line 21\r\n     19 fig.colorbar(cs0, ax=[axes[\"A\"], axes[\"B\"]], location=\"right\")\r\n     20 axes[\"C\"].plot(x)\r\n---\u003e 21 pd.DataFrame(x).plot(ax=axes[\"C\"])\r\n     22 # fig.colorbar(cs0, ax=[axes[\"A\"], axes[\"B\"]], location=\"right\")\r\n\r\nFile ~/micromamba/envs/TEST/lib/python3.11/site-packages/pandas/plotting/_core.py:1000, in PlotAccessor.__call__(self, *args, **kwargs)\r\n    997             label_name = label_kw or data.columns\r\n    998             data.columns = label_name\r\n-\u003e 1000 return plot_backend.plot(data, kind=kind, **kwargs)\r\n\r\nFile ~/micromamba/envs/TEST/lib/python3.11/site-packages/pandas/plotting/_matplotlib/__init__.py:71, in plot(data, kind, **kwargs)\r\n     69         kwargs[\"ax\"] = getattr(ax, \"left_ax\", ax)\r\n     70 plot_obj = PLOT_CLASSES[kind](data, **kwargs)\r\n---\u003e 71 plot_obj.generate()\r\n     72 plot_obj.draw()\r\n     73 return plot_obj.result\r\n\r\nFile ~/micromamba/envs/TEST/lib/python3.11/site-packages/pandas/plotting/_matplotlib/core.py:455, in MPLPlot.generate(self)\r\n    453 self._add_table()\r\n    454 self._make_legend()\r\n--\u003e 455 self._adorn_subplots()\r\n    457 for ax in self.axes:\r\n    458     self._post_plot_logic_common(ax, self.data)\r\n\r\nFile ~/micromamba/envs/TEST/lib/python3.11/site-packages/pandas/plotting/_matplotlib/core.py:679, in MPLPlot._adorn_subplots(self)\r\n    677     all_axes = self._get_subplots()\r\n    678     nrows, ncols = self._get_axes_layout()\r\n--\u003e 679     handle_shared_axes(\r\n    680         axarr=all_axes,\r\n    681         nplots=len(all_axes),\r\n    682         naxes=nrows * ncols,\r\n    683         nrows=nrows,\r\n    684         ncols=ncols,\r\n    685         sharex=self.sharex,\r\n    686         sharey=self.sharey,\r\n    687     )\r\n    689 for ax in self.axes:\r\n    690     ax = getattr(ax, \"right_ax\", ax)\r\n\r\nFile ~/micromamba/envs/TEST/lib/python3.11/site-packages/pandas/plotting/_matplotlib/tools.py:410, in handle_shared_axes(axarr, nplots, naxes, nrows, ncols, sharex, sharey)\r\n    408 layout = np.zeros((nrows + 1, ncols + 1), dtype=np.bool_)\r\n    409 for ax in axarr:\r\n--\u003e 410     layout[row_num(ax), col_num(ax)] = ax.get_visible()\r\n    412 for ax in axarr:\r\n    413     # only the last row of subplots should get x labels -\u003e all\r\n    414     # other off layout handles the case that the subplot is\r\n    415     # the last in the column, because below is no subplot/gap.\r\n    416     if not layout[row_num(ax) + 1, col_num(ax)]:\r\n\r\nFile ~/micromamba/envs/TEST/lib/python3.11/site-packages/pandas/plotting/_matplotlib/tools.py:396, in handle_shared_axes.\u003clocals\u003e.\u003clambda\u003e(x)\r\n    386 def handle_shared_axes(\r\n    387     axarr: Iterable[Axes],\r\n    388     nplots: int,\r\n   (...)\r\n    393     sharey: bool,\r\n    394 ):\r\n    395     if nplots \u003e 1:\r\n--\u003e 396         row_num = lambda x: x.get_subplotspec().rowspan.start\r\n    397         col_num = lambda x: x.get_subplotspec().colspan.start\r\n    399         if compat.mpl_ge_3_4_0():\r\n\r\nAttributeError: 'NoneType' object has no attribute 'rowspan'\r\n```\n\n### Expected outcome\n\n![Screenshot from 2023-03-23 15-21-12](https://user-images.githubusercontent.com/950575/227310711-a33f7cfa-19c8-412a-872c-840f4b51ac5a.png)\n\n### Additional information\n\n_No response_\n\n### Operating system\n\n_No response_\n\n### Matplotlib Version\n\n3.7.0 and 3.7.1\n\n### Matplotlib Backend\n\nmodule://matplotlib_inline.backend_inline\n\n### Python version\n\n3.11\n\n### Jupyter version\n\n6.5.3\n\n### Installation\n\nconda","author":{"url":"https://github.com/ocefpaf","@type":"Person","name":"ocefpaf"},"datePublished":"2023-03-23T18:23:13.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/25538/matplotlib/issues/25538"}