Series.hist resulting series name changes with include_breakpoint=False, include_category=False about polars HOT 2 OPEN

This is a side-effect of porting the method from Expr to Series.

For Expr, the resulting expression is named "a" in all cases, but when include_breakpoint=True the return data type is a Struct and the fields are named breakpoint/count. Because we expand that struct to a dataframe in the Series method, the original name is lost.

I think the best solution would be to just follow Expr here and return a Struct Series, not a DataFrame. That's how cut/qcut work at the moment. What would you think of that solution?

hist is sort-of modeled after cut/qcut, but we aim to overhaul that API so that is not very helpful either.

from polars.

Returning a struct series seems fine to me.

from polars.