René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: bbox_inches='tight' works differently when ax.plot() have markers","articleBody":"### Bug summary\n\nHello.\n\nThis is a minimal code:\n\n```python\n# type: ignore\n\nimport matplotlib.pyplot as plt\nfrom matplotlib.transforms import Affine2D, ScaledTranslation, BlendedGenericTransform\n\nL = 755\n\nfig, axes = plt.subplots(nrows=3, ncols=1, dpi=150)\n\nfor ax in axes:\n    ax.margins(x=0)\n    ax.set_xlim((0, L))\n\nax = axes[-1]\n\ntr = BlendedGenericTransform(\n    x_transform=ax.transData,\n    y_transform=ax.transAxes + ScaledTranslation(0, -355, Affine2D())\n)\n\nax.plot(\n    [0, L],\n    [0, 0],\n    lw=1.4,\n    c='black',\n    clip_on=False,\n    transform=tr,\n    marker='o',   # \u003c--- (1)\n    markersize=3, # \u003c--- (2)\n    zorder=10\n)\n\nplt.show()\n```\n\nI run this in VS Code Notebook (`%config InlineBackend.print_figure_kwargs = {'bbox_inches':'tight'}`), and this code produces image I expected:\n\n\u003cimg width=\"855\" height=\"950\" alt=\"Image\" src=\"https://github.com/user-attachments/assets/d330c35e-1fd4-4efb-96e7-ba75b385c277\" /\u003e\n\nFigure sizes are changed automatically so we see horizontal line at the bottom of this figure.\n\nThen I make a small change for `ax.plot`: I comment `marker=...` and `markersize=...` ((1) and (2) in code above). After that small change figure stop to include horizontal line:\n\n\u003cimg width=\"852\" height=\"626\" alt=\"Image\" src=\"https://github.com/user-attachments/assets/14f98278-1317-401e-9953-a00452016da0\" /\u003e\n\nNot sure, if it is a bug, but this is definitelly very strange.\n\n### Code for reproduction\n\n```Python\n# type: ignore\n\nimport matplotlib.pyplot as plt\nfrom matplotlib.transforms import Affine2D, ScaledTranslation, BlendedGenericTransform\n\nL = 755\n\nfig, axes = plt.subplots(nrows=3, ncols=1, dpi=150)\n\nfor ax in axes:\n    ax.margins(x=0)\n    ax.set_xlim((0, L))\n\nax = axes[-1]\n\ntr = BlendedGenericTransform(\n    x_transform=ax.transData,\n    y_transform=ax.transAxes + ScaledTranslation(0, -355, Affine2D())\n)\n\nax.plot(\n    [0, L],\n    [0, 0],\n    lw=1.4,\n    c='black',\n    clip_on=False,\n    transform=tr,\n    # marker='o',   # \u003c--- comment this line to make line outside figure boundaries\n    # markersize=3, # \u003c--- comment this line to make line outside figure boundaries\n    zorder=10\n)\n\nplt.show()\n```\n\n### Actual outcome\n\nWhen I comment `marker=...` and `markersize=...` in `ax.plot(...)`, horizontal line is out of figure boundaries.\n\n\u003cimg width=\"852\" height=\"626\" alt=\"Image\" src=\"https://github.com/user-attachments/assets/14f98278-1317-401e-9953-a00452016da0\" /\u003e\n\n### Expected outcome\n\nI expect figure changes its sizes to include horizontal line as shown below:\n\n\u003cimg width=\"855\" height=\"950\" alt=\"Image\" src=\"https://github.com/user-attachments/assets/d330c35e-1fd4-4efb-96e7-ba75b385c277\" /\u003e\n\n### Additional information\n\n_No response_\n\n### Operating system\n\nWindows 10\n\n### Matplotlib Version\n\n3.10.7\n\n### Matplotlib Backend\n\n'module://matplotlib_inline.backend_inline'\n\n### Python version\n\n3.13.7\n\n### Jupyter version\n\n_No response_\n\n### Installation\n\npip","author":{"url":"https://github.com/sindzicat","@type":"Person","name":"sindzicat"},"datePublished":"2025-10-28T09:55:18.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/30695/matplotlib/issues/30695"}