René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: Spurious lines added with some manually add contour labels","articleBody":"### Bug summary\n\nWith Matplotlib 3.8+ I'm seeing spurious lines that get added with manually labeled contours via `clabel`.\r\n\r\nIt seems to only happen in locations where the contours are more complex or near those areas, but I haven't been able to track down why this happens.  \n\n### Code for reproduction\n\n```python\nExample code (here working with Matplotlib \u003c3.8): https://geocat-examples.readthedocs.io/en/latest/gallery/Contours/NCL_coneff_8.html\r\n\r\nI'll work on stripping down this example though.\n```\n\n\n### Actual outcome\n\nwhen run in a script that provided a manual list of contour label locations:\r\n\u003cimg width=\"623\" alt=\"Screen Shot 2023-11-15 at 3 17 14 PM\" src=\"https://github.com/matplotlib/matplotlib/assets/7872563/a5815b2f-3160-4f10-a9ac-03894c203314\"\u003e\r\n\r\nwhen locations were manually clicked:\r\n\u003cimg width=\"763\" alt=\"Screen Shot 2023-11-15 at 3 21 19 PM\" src=\"https://github.com/matplotlib/matplotlib/assets/7872563/10f083da-5845-46a0-98ea-c6eb47371d23\"\u003e\r\n\r\n\n\n### Expected outcome\n\nsimilar, but without the spurious straight lines.\n\n### Additional information\n\nWhat are the conditions under which this bug happens?\r\n* happens with both \"clicked\" and specified manual contour labels in certain locations\r\n* seems to happen only near areas with more complex contours\r\n* interestingly, this also happens when you specify contour label locations this way on a cartopy map and the specified points are not on the projected map.  however, this is not the case here.\r\nHas this worked in earlier versions?\r\n* worked prior to 3.8\r\nDo you know why this bug is happening?\r\n* unfortunately, no.  will look into it a bit more though.\r\n\n\n### Operating system\n\nOS/X\n\n### Matplotlib Version\n\n3.8.1\n\n### Matplotlib Backend\n\nMacOSX\n\n### Python version\n\nPython 3.11.6\n\n### Jupyter version\n\n4.0.8\n\n### Installation\n\nconda","author":{"url":"https://github.com/kafitzgerald","@type":"Person","name":"kafitzgerald"},"datePublished":"2023-11-15T22:41:18.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/27333/matplotlib/issues/27333"}