ENH: Standardized timeseries accessor names, #9606

[emilydolson]

In accordance with #9606, I added day_of_week and day_of_year accessors to DatetimeIndex, Timestamp, and Period. Since #9606 didn't mention weekofyear, and there's already week as a replacement for that, I didn't add a week_of_year, but I'm happy to.

I updated the tests and docs, but this is my first PR to pandas involving actual code, so let me know if I missed anything.

[jorisvandenbossche]

For dayofweek/day_of_week we also already have weekday, so this is adding a third alias for that one ..
So I am a bit torn on this one (although I like the fact that we try to standardize the namings)

[jreback]

@jorisvandenbossche I think we should deprecate the original ones in 0.18 anyhow (eg daysinmonth)

[jreback]

let's switch the impl to the new names (and make the original ones aliases)
that way they are easy to remove

[jorisvandenbossche]

Maybe we could also remove these from the dir to avoid all the duplicates in tab completion?

[jreback]

there is a test in test_series for dt accessor that needs updating as well

[jreback]

yep @jorisvandenbossche agreed

[jorisvandenbossche]

I think choosing one prefered name per attribute, and remove all others from the docs (only mentioning them somewhere as being aliases) and tab completion, is maybe a less 'aggresive' way for striving for consistency instead of really deprecating them

[jreback]

sure that's fine too

[jreback]

@emilydolson you will need to define

def _dir_deletions()

which returns a set of the attributes to remove

[emilydolson]

I've got the tab completion fixed for DatetimeIndex and PeriodIndex, but defining _dir_deletions() in Timestamp doesn't seem to affect the return value of __dir__(). Is there something about Cython that might interfere with _dir_deletions?

[jreback]

so the issue here is that Timestamp needs to inherit from PandasObject, which is in pandas.core.base. But you can't simply include that as it would have a circular dependency.

So here is what we need to do.

Move from pandas.core.base, StringMixin and PandasObject to a new module, call it pandas.core.object. import this to pandas.core.base (you may want to change imports of PandasObject elsewhere in the codebase). Then you can import this as a mix-in for Timestamp (in tslib.pyx).

long-story-short this will then work.

[jreback]

can you rebase / update

also let's deprecate the old names (e.g. w/o the underscores).

You will need to put the warning in the accessor (and probably create a specific function/property for them in order to do this as they are defined by the _field_accessor ATM)

[jreback]

can you update

[jreback]

@emilydolson can you rebase/update according to comments

[jreback]

@emilydolson can you rebase/update according to comments

[jreback]

closing, but pls reopen if you'd like to update, which would be great.