DEPR: NDFrame.to_period, to_timestamp, tz_localize, tz_convert

[jbrockmendel]

These are methods that operate on the index/columns, not the series/frame values. We could deprecate in favor of e.g. obj.set_axis(obj.index.to_timestamp(), axis=0)

[topper-123]

#52023 was about adding a generic method for getting axes. Doing this + doing #52023 would IMO be much more flexible than the current situation and we wouldn’t need specific index methods on ndframes.

EDIT: changed "setting" to "getting".

[topper-123]

I'm +1 on deprecating those methods. i can never remember which index methods are mirrored in the ndframe, so I always end up just doing

df = df.copy()  # if I don't want to keep the old frame
df.index = df.index.tz_localize(tz)

IMO a set_axis method would be nice if it could be used in a pipe. For that to work, the first argument should be either an indexlike or a callable, so something like piped_df.set_index(lambda x: x.tz_localize(tz), axis="index") and piped_df.set_index(pd.Index(...), axis="index") could both work.

We have a lot of index methods and only some will feature in the axis_ops namespace and it's not intuitive why those have been selected and others not. so it's same problem as beforehand for me. What about adding a set_index method and skipping axis_ops?