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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"QuadMesh.get_clim changed behavior in 3.3.0rc1","articleBody":"### Bug report\r\n\r\n**Bug summary**\r\n\r\n`QuadMesh.get_clim()` is documented as:\r\n\u003e Return the values (min, max) that are mapped to the colormap limits.\r\n\r\nWithout `vmin` or `vmax` arguments to `pcolormesh`, this returns the data minimal and maximal values. However in the presence of only one of `vmin` or `vmax`, a change occurred between 3.2.2 and 3.3.0rc1. In 3.3.0rc1 it returns the input vmin *and* vmax, though only one of them was specified. The provided examples also happens (with slight output changes) for setting `vmax` instead of vmin.\r\n\r\n**Code for reproduction**\r\n\r\n```python\r\nimport numpy as np\r\nimport matplotlib.pyplot as plt\r\n\r\ndx, dy = 0.15, 0.05\r\ny, x = np.mgrid[slice(-3, 3 + dy, dy),\r\n                slice(-3, 3 + dx, dx)]\r\nz = (1 - x / 2. + x ** 5 + y ** 3) * np.exp(-x ** 2 - y ** 2)\r\nz = z[:-1, :-1]\r\n\r\nf, ax = plt.subplots(1,1)\r\nax.pcolormesh(x, y, z, vmin=0)\r\nax.axis([x.min(), x.max(), y.min(), y.max()])\r\nfor mesh in ax.collections:\r\n    print(mesh.get_clim())\r\n```\r\n\r\n**Actual outcome**\r\n\r\n```\r\n# 3.3.0rc1\r\n(0.0, None)\r\n```\r\n\r\n**Expected outcome**\r\n```\r\n# 3.2.2\r\n(0.0, 1.0510083319982622)\r\n```\r\n\r\n**Matplotlib version**\r\n  * Operating system: MacOSX\r\n  * Matplotlib version: 3.3.0rc1\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): MacOSX\r\n  * Python version: 3.8.3\r\n\r\n\u003c!--Please tell us how you installed matplotlib and python e.g., from source, pip, conda--\u003e\r\n\u003c!--If you installed from conda, please specify which channel you used if not the default--\u003e\r\nInstalled using pip\r\n","author":{"url":"https://github.com/MaozGelbart","@type":"Person","name":"MaozGelbart"},"datePublished":"2020-06-21T08:12:37.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/17703/matplotlib/issues/17703"}