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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Plot_date default date format is not always the same","articleBody":"\r\n\r\n\r\n### Bug report\r\n\r\n**Bug summary**\r\n\r\nIn the example below date format is changed when plotting with plot_date after calling dates.DayLocator(). This can be fixed with using dates.DateFormatter(), but the confusion could be avoided if plot_date uses the same date format when it is not specified by user.\r\n\r\n\r\n**Code for reproduction**\r\n\u003c!--A minimum code snippet required to reproduce the bug, also minimizing the number of dependencies required--\u003e\r\n\r\n```python\r\nimport datetime\r\nimport matplotlib.pyplot as plt\r\nimport matplotlib.dates as mdates\r\n\r\nDATE1 = mdates.date2num(datetime.datetime(2017, 8, 10, 18, 0))\r\nDATE2 = mdates.date2num(datetime.datetime(2017, 8, 11, 18, 0))\r\nDATE3 = mdates.date2num(datetime.datetime(2017, 8, 12, 18, 0))\r\nplt.plot_date([DATE1, DATE2, DATE3], [1, 2, 3], '-')\r\nplt.show()\r\n\r\nplt.plot_date([DATE1, DATE2, DATE3], [1, 2, 3], '-')\r\nplt.gca().xaxis.set_major_locator(mdates.DayLocator())\r\nplt.show()\r\n```\r\n\r\n**Actual outcome**\r\n\r\n\u003cimg width=\"575\" alt=\"beforedaylocator\" src=\"https://user-images.githubusercontent.com/14822000/32735913-638bd714-c896-11e7-9f4b-94752e53e3e4.png\"\u003e\r\n\r\n\u003cimg width=\"584\" alt=\"afterdaylocator\" src=\"https://user-images.githubusercontent.com/14822000/32735922-6a0b0aa6-c896-11e7-93be-00c99b04d7ae.png\"\u003e\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: Mac OS\r\n  * Matplotlib version:  2.0.2\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`):\r\n  * Python version: 2.7.13\r\n  * Jupyter version (if applicable):\r\n  * Other libraries: \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/mirkocoric","@type":"Person","name":"mirkocoric"},"datePublished":"2017-11-13T16:19:08.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/9765/matplotlib/issues/9765"}