René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Contours are not removed correctly when using clabel with manual","articleBody":"### Bug report\r\n\r\n**Bug summary**\r\n\r\nContours created using `pyplot.contour` are not correctly removed when labelling the contours using`plt.clabel` invoked with `inline=True` and manual positions.\r\n\r\n**Code for reproduction**\r\n\r\n```python\r\nimport numpy as np\r\nfrom matplotlib import pyplot as plt\r\n\r\nx = np.linspace(-1, 1)\r\nxx, yy = np.meshgrid(x, x)\r\n\r\nfig, axes = plt.subplots(1, 2, True, True)\r\n\r\nmanual = None\r\nfor ax in axes:\r\n    cs = ax.contour(x, x, xx ** 2 + yy ** 2)\r\n    clabels = plt.clabel(cs, manual=manual)\r\n    manual = [label.get_position() for label in clabels]\r\n```\r\n\r\n**Expected outcome on the left, actual outcome on the right**\r\n\r\n![image](https://user-images.githubusercontent.com/966348/33913033-128b6e54-df90-11e7-88b5-7ac859334edf.png)\r\n\r\n**Matplotlib version**\r\n\r\n  * Operating system: Linux 273ceb986a84 4.9.49-moby #1 SMP Wed Sep 27 23:17:17 UTC 2017 x86_64 GNU/Linux\r\n  * Matplotlib version: 2.1.1\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): module://ipykernel.pylab.backend_inline\r\n  * Python version: 3.6.3\r\n  * Jupyter version (if applicable): 4.4.0\r\n  * Other libraries: numpy (1.13.3)\r\n\r\nAll libraries were installed using pip in a docker image derived from `python:3`.\r\n","author":{"url":"https://github.com/tillahoffmann","@type":"Person","name":"tillahoffmann"},"datePublished":"2017-12-12T23:02:26.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/9988/matplotlib/issues/9988"}