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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Should xlim support single-entry arrays?","articleBody":"There is one change in behaviour I noticed when upgrading to Python 3.8, where matplotlib 3.1.1  used to work in Python 3.7, but not in Python 3.8 any more.\r\n\r\n```\r\n\u003e\u003e\u003e import numpy as np\r\n\u003e\u003e\u003e import matplotlib.pyplot as plt\r\n\u003e\u003e\u003e plt.xlim(np.array([3]), 4)\r\nTraceback (most recent call last):\r\n  File \"\u003cstdin\u003e\", line 1, in \u003cmodule\u003e\r\n  File \"/Users/deil/opt/anaconda3/envs/py38/lib/python3.8/site-packages/matplotlib/pyplot.py\", line 1434, in xlim\r\n    ret = ax.set_xlim(*args, **kwargs)\r\n  File \"/Users/deil/opt/anaconda3/envs/py38/lib/python3.8/site-packages/matplotlib/axes/_base.py\", line 3270, in set_xlim\r\n    left, right = sorted([left, right], reverse=reverse)\r\nTypeError: only integer scalar arrays can be converted to a scalar index\r\n```\r\n\r\nI think the issue is that `reverse = np.array([False])` and `sorted` refuses to process that, raising the `TypeError`. I'm not sure if this is a change in behaviour in CPython, or if I'm having slightly different Numpy \u0026 matplotlib versions in my Python 3.7 and 3.8 environments.\r\n\r\nIn our scripts we have code that computes the `left` and `right` for `set_xlim`, and for complex reasons it gives a 1-element `ndim=1` Numpy array, not a Numpy scalar.\r\n\r\nNow the docstring says that only scalar is supported:\r\nhttps://matplotlib.org/3.1.1/api/_as_gen/matplotlib.axes.Axes.set_xlim.html\r\n\r\nIs the old behaviour to work OK with single-entry `ndim=1` arrays something you want to support via some code change in `matplotlib`?\r\nOr is this a usage bug that only accidentally worked earlier, and we fix our code?","author":{"url":"https://github.com/cdeil","@type":"Person","name":"cdeil"},"datePublished":"2019-11-13T08:50:58.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/15690/matplotlib/issues/15690"}