René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: Crash when adding clabels to subfigures","articleBody":"### Bug summary\n\nAdding a clabel to a contour plot of a subfigure results in a traceback.\n\n### Code for reproduction\n\n```python\n# Taken from the Contour Demo example\r\ndelta = 0.025\r\nx = np.arange(-3.0, 3.0, delta)\r\ny = np.arange(-2.0, 2.0, delta)\r\nX, Y = np.meshgrid(x, y)\r\nZ1 = np.exp(-(X**2) - Y**2)\r\nZ2 = np.exp(-((X - 1) ** 2) - (Y - 1) ** 2)\r\nZ = (Z1 - Z2) * 2\r\n\r\nfig = plt.figure()\r\nfigs = fig.subfigures(nrows=1, ncols=2)\r\n\r\nfor f in figs:\r\n    ax = f.subplots()\r\n    CS = ax.contour(X, Y, Z)\r\n    ax.clabel(CS, inline=True, fontsize=10)\r\n    ax.set_title(\"Simplest default with labels\")\r\n\r\nplt.show()\n```\n\n\n### Actual outcome\n\n```\r\n    ax.clabel(CS, inline=True, fontsize=10)\r\n  File \"/usr/lib/python3.9/site-packages/matplotlib/axes/_axes.py\", line 6335, in clabel\r\n    return CS.clabel(levels, **kwargs)\r\n  File \"/usr/lib/python3.9/site-packages/matplotlib/contour.py\", line 235, in clabel\r\n    self.labels(inline, inline_spacing)\r\n  File \"/usr/lib/python3.9/site-packages/matplotlib/contour.py\", line 582, in labels\r\n    lw = self._get_nth_label_width(idx)\r\n  File \"/usr/lib/python3.9/site-packages/matplotlib/contour.py\", line 285, in _get_nth_label_width\r\n    .get_window_extent(mpl.tight_layout.get_renderer(fig)).width)\r\n  File \"/usr/lib/python3.9/site-packages/matplotlib/tight_layout.py\", line 206, in get_renderer\r\n    if fig._cachedRenderer:\r\nAttributeError: 'SubFigure' object has no attribute '_cachedRenderer'\r\n```\n\n### Expected outcome\n\nThe two subfigures appearing side by side, each showing the Contour Demo example\n\n### Additional information\n\n_No response_\n\n### Operating system\n\nGentoo\n\n### Matplotlib Version\n\n3.5.2\n\n### Matplotlib Backend\n\nQtAgg\n\n### Python version\n\n3.9.13\n\n### Jupyter version\n\n_No response_\n\n### Installation\n\nLinux package manager","author":{"url":"https://github.com/brckts","@type":"Person","name":"brckts"},"datePublished":"2022-06-01T09:33:02.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/23173/matplotlib/issues/23173"}