QST: use and breadth of x_compat=True

[ptoche]

Research

• I have searched the [pandas] tag on StackOverflow for similar questions.

• I have asked my usage related question on StackOverflow.

Link to question on StackOverflow

https://stackoverflow.com/questions/70707996/matplotlib-horizontal-labels-as-style?noredirect=1#comment125004119_70707996

Question about pandas

If I understand correctly, x_compat=True allows one to have access to matplotlib's date formatters and disables some of pandas's date formatting. However, it has no effect on rotation (or rot in pandas parlance). My question is whether one would expect x_compat=True to also disable the rotation (that is, set it to 0). In other words, I'm not clear on how much of the date formatting x_compat=True is expected to "return" to the matplotlib default. Was it a design decision?

[MarcoGorelli]

My question is whether one would expect x_compat=True to also disable the rotation (that is, set it to 0)

Not sure I understand the question - doesn't x_compat=True result in rotated labels? Can you show an example please?

[ptoche]

Thanks for your question!

Well I may be misunderstanding. Here's what I thought happened: with df.plot() a number of default are set, including handling of dates and rotating long dates such as "2021-01-01" by 30 degrees, but the x_compat=True flag allows the user to disable these defaults and call the matplotlib locators and formatters. Am I misunderstanding?

Setting x_compat=True keeps the rotation at 30 degrees, when I expected it to be reset to the matlolib default of 0 degrees.

I'm currently setting the rotation to 0 inside the plot call, but I would have liked for it to have been a default. Not a big deal.

[MarcoGorelli]

I think x_compat is more about tick location than about format, so I presume they thought the 30 degree rotation would still be a sensible default

You could start looking through #2205 and 8d45dc4 for more info

Anyway, regardless of the design decision which was taken 10 years ago, it's probably not worth changing this now

[ptoche]

The label's orientation feels like something distinct from the locator/formatter, maybe similar to the choice of font type and size. That's why I expected to be able to control it as a style, rather than within the call to plot. But yes, I'll just forget about this.