René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"axes.format_{x,y} data should have a setter","articleBody":"In the [Date tick labels](https://matplotlib.org/3.1.1/gallery/text_labels_and_annotations/date.html#sphx-glr-gallery-text-labels-and-annotations-date-py) example, the code for setting the cursor coords message overwrites the default formatters:\r\n```python\r\nax.format_xdata = mdates.DateFormatter('%Y-%m-%d')\r\nax.format_ydata = lambda x: '$%1.2f' % x  # format the price.\r\n```\r\nThis creates confusion because runs counter to how basically everything else in matplotlib is set via setter but especially the formatters:\r\n```python\r\nax.xaxis.set_major_formatter(mdates.DateFormatter('%Y'))\r\n```\r\nand [the docs](https://matplotlib.org/3.1.1/api/_as_gen/matplotlib.axes.Axes.format_xdata.html?highlight=format_xdata#matplotlib.axes.Axes.format_xdata) aren't especially clear either on this being a property:\r\n```\r\nAxes.format_xdata(self, x)\r\n\r\n    Return x formatted as an x-value.\r\n\r\n    This function will use the fmt_xdata attribute if it is not None, else will fall back on the xaxis major formatter.\r\n```\r\nTo be consistent with the API, I'm proposing properties/functions of the form:\r\n* `ax.{x,y}data_formatter(mdates.DateFormatter('%Y-%m-%d'))`\r\n* `ax.data_formatter(which=(x,y, both), mdates.DateFormatter('%Y-%m-%d'))`\r\n\r\n","author":{"url":"https://github.com/story645","@type":"Person","name":"story645"},"datePublished":"2020-04-30T22:28:16.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/17286/matplotlib/issues/17286"}