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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Use data argument for scatter plotting timestamps from pandas","articleBody":"\u003c!--To help us understand and resolve your issue, please fill out the form to the best of your ability.--\u003e\r\n\u003c!--You can feel free to delete the sections that do not apply.--\u003e\r\n\r\n### Bug report\r\n\r\n**Bug summary**\r\n\r\nThis may be either a bug report or a feature request, depending how you view things. The issue is that you cannot use the `data` argument to `scatter` to plot a pandas dataframe `Timestamp` column.\r\n\r\n**Code for reproduction**\r\n\r\nConsider the following data\r\n\r\n```\r\nimport matplotlib.pyplot as plt\r\nimport pandas as pd\r\nimport numpy as np; np.random.seed(42)\r\n\r\ndf = pd.DataFrame(np.random.rand(10,2), columns=[\"x\",\"y\"])\r\ndf[\"time\"] = pd.date_range(\"2018-01-01\", periods=10, freq=\"D\")\r\n```\r\n\r\n\r\nUsing the `data` argument, you may plot\r\n\r\n    plt.plot(\"x\", \"y\", data=df)\r\n\r\nYou may equally plot\r\n\r\n    plt.plot(\"time\", \"y\", data=df)\r\n\r\nYou may also scatter\r\n\r\n    plt.scatter(x=\"x\", y=\"y\", data=df)\r\n\r\n**However, you may not scatter the timestamps**\r\n\r\n    plt.scatter(x=\"time\", y=\"y\", data=df)\r\n\r\nThis fails with a `TypeError: invalid type promotion`\r\n\r\n```\r\nTraceback (most recent call last):\r\n  File \"D:/.../test/GI_scatterdataarg.py\", line 40, in \u003cmodule\u003e\r\n    plt.scatter(x=\"time\", y=\"y\", data=df)\r\n  File \"d:\\...\\matplotlib\\lib\\matplotlib\\pyplot.py\", line 2623, in scatter\r\n    verts=verts, edgecolors=edgecolors, data=data, **kwargs)\r\n  File \"d:\\...\\matplotlib\\lib\\matplotlib\\__init__.py\", line 1775, in inner\r\n    return func(ax, *args, **kwargs)\r\n  File \"d:\\...\\matplotlib\\lib\\matplotlib\\axes\\_axes.py\", line 3982, in scatter\r\n    offsets = np.column_stack([x, y])\r\n  File \"D:\\...\\matplotlib\\lib\\site-packages\\numpy\\lib\\shape_base.py\", line 369, in column_stack\r\n    return _nx.concatenate(arrays, 1)\r\nTypeError: invalid type promotion\r\n```\r\n\r\nThis is a bit surprising since you may well plot timestamps through scatter\r\n\r\n    plt.scatter(x=df.time.values, y=df.x.values)\r\n\r\njust not through the `data` argument. \r\n\r\n**Expected outcome**\r\n\r\nGiven that one may plot the timestamps correctly with `plot` and timestamps with `scatter` by providing the values, it would be nice to be able to use the `data` argument with `scatter` as well.\r\n\r\n... and ideally with `bar`, `fill_between` etc. ;-)\r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system: Win 8.1\r\n  * Matplotlib version: master 2.2.2.post1270+g6665bc739\r\n  * Matplotlib backend: Qt5Agg\r\n  * Python version: 3.6\r\n  * Jupyter version (if applicable):\r\n  * Other libraries: Pandas 0.22.0\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\n\r\n","author":{"url":"https://github.com/ImportanceOfBeingErnest","@type":"Person","name":"ImportanceOfBeingErnest"},"datePublished":"2018-06-06T22:53:03.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":15},"url":"https://github.com/11391/matplotlib/issues/11391"}