ENH: Add `index=`/`columns=` kwargs to `df.set_axis()`

[wany-oh]

I think it is strange that .set_axis() can't accept index=/columns= kwargs, even though similar methods .rename(), .rename_axis(), .drop() and etc. can.

Personally, I think it would be more readable than specifying it with 0 or 1.
One trivial advantage is that it allows us to change rows and columns at once.

expect:

>>> df = pd.DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]})
>>> df.set_axis(index=['a', 'b', 'c'])
   A  B
a  1  4
b  2  5
c  3  6

>>> df.set_axis(columns=['I', 'II'])
   I  II
0  1   4
1  2   5
2  3   6

>>> df.set_axis(index=['a', 'b', 'c'], columns=['I', 'II'])
   I  II
a  1   4
b  2   5
c  3   6

[rhshadrach]

+1 for the API consistency here.

[leonarduschen]

take

[leonarduschen]

How should this work with Series?

Consideration:

• DataFrame.rename signature:

  def rename(
      self,
      mapper: Renamer | None = None,
      *,
      index: Renamer | None = None,
      columns: Renamer | None = None,
      axis: Axis | None = None,
      copy: bool = True,
      inplace: bool = False,
      level: Level | None = None,
      errors: IgnoreRaise = "ignore",
  ) -> DataFrame | None:

• Series.rename signature:

  def rename(
      self,
      index: Renamer | Hashable | None = None,
      *,
      axis: Axis | None = None,
      copy: bool = True,
      inplace: bool = False,
      level: Level | None = None,
      errors: IgnoreRaise = "ignore",
  ) -> Series | None:

Series.rename accepts all signature of DataFrame.rename except for mapper and columns (documentation is wrong, already reported at #46889)

Currently, we have DataFrame.set_axis and Series.set_axis current signature:

def set_axis(self, labels, axis: Axis = 0, inplace: bool = False):

We'll add index and columns to DataFrame.set_axis:

def set_axis(self, labels, index, columns, axis: Axis = 0, inplace: bool = False):

I think we shouldn't make any change to Series.set_axis. It still wouldn't be 100% consistent with .rename since Series.rename accepts index instead of mapper, but I don't think there's any way around it.

[rhshadrach]

Agreed on not changing Series.set_axis (similar to how Series.rename doesn't have columns). I may be misunderstanding, but I don't think there should be consistency with mapper for Series.rename; supplying a mapper to Series.rename doesn't make sense.

[jbrockmendel]

I think its a good thing that set_axis has One Obvious Way to be called, and a bad thing that other methods have multiple valid ways to do the same thing. -1 on changing here.

[rhshadrach]

Personally, I think it would be more readable than specifying it with 0 or 1.

As the documentation states, one can also use 'index' and 'columns'. I think that takes care of the readability argument. The only other argument I see is being able to set both in a single rather than two calls, which I personally find negligible. Agree with @jbrockmendel we should prefer simplicity here. Closing.