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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"time series plotting gap causes strange jump","articleBody":"# Bug report\r\nGap in time series data causes MPL to jump to a very small datetime that doesnt exist in the dataset.\r\n![image](https://user-images.githubusercontent.com/25716039/72686717-97ebc200-3ac5-11ea-8f37-4953d6a85de6.png)\r\n\r\nIf I don't manually set the axis, it tries to autofit.\r\n```\r\nax1.set_xlim( [ min(datana.date.dt.to_pydatetime()) , max(datana.date.dt.to_pydatetime()) ])\r\n```\r\nAutofitting looks like this:\r\n![image](https://user-images.githubusercontent.com/25716039/72686749-daad9a00-3ac5-11ea-8ef1-d3b921936987.png)\r\n\r\nNote that the minimum x datetime in the dataset is in 2019! Not sure where the 1680ish time comes from. I've manually checked what actually gets passed into mpl, a numpy object array of datetime objects, does not have a time value below 2019.\r\n\r\nAbbreviated code:\r\n```\r\nimport datetime\r\nimport time\r\nimport matplotlib\r\nmatplotlib.use(\"agg\")\r\nimport matplotlib.pyplot as plt\r\nimport pandas as pd\r\n\r\nfig1, ax1 = plt.subplots( figsize=(15,5) )\r\n\r\n    data = pd.read_csv(\"temps.dat\",header=None, names=['date','temp'])\r\n    data.temp = data.temp/1000\r\n    data.date = pd.to_datetime(data.date)\r\n    data.date = data.date.dt.ceil(freq='s') #strip microseconds\r\n    data['roll'] = data['temp'].rolling(window=722 ).mean()\r\n    data['roll2'] = data['temp'].rolling(window=14220  ).mean()\r\n    datana = data.dropna(subset=['roll'])\r\n    datana2 = data.dropna(subset=['roll2'])\r\n\r\n    ax1.cla()\r\n \r\n    ax1.plot(datana2.date.dt.to_pydatetime()  ,datana2.roll2, lw=3, alpha=.8)\r\n    ax1.plot(datana.date.dt.to_pydatetime()  ,datana.roll, lw=.7)\r\n\r\n    ax1.set_xlim( [ min(datana.date.dt.to_pydatetime()) , max(datana.date.dt.to_pydatetime()) ])\r\nfig1.autofmt_xdate()\r\nfig1.savefig(\"fig1.png\",format='png' ,bbox_inches='tight', dpi=500)\r\n\r\n```\r\n[temps.zip](https://github.com/matplotlib/matplotlib/files/4083375/temps.zip)\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: debian (raspbian)\r\n  * Matplotlib version:  3.1.2 , in a venv, installed by pip\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): agg\r\n  * Python version: 3.7\r\n \r\n  * Other libraries: pandas, Pillow\r\n\r\n\r\n","author":{"url":"https://github.com/Fealthas","@type":"Person","name":"Fealthas"},"datePublished":"2020-01-19T19:21:47.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/16266/matplotlib/issues/16266"}