ARROW-14825: [C++] Temporal component extraction function for extracting epiyear

[rok]

This is to resolve ARROW-14825.

[github-actions]

https://issues.apache.org/jira/browse/ARROW-14825

[rok]

Would us_year be a better name as it's consistent with already present us_week name?

[lidavidm]

us_year seems to better in that regard. (Looking it up - it turns out "epiweek" means something different in the US vs the rest of the world? Oof.)

[rok]

us_year seems to better in that regard. (Looking it up - it turns out "epiweek" means something different in the US vs the rest of the world? Oof.)

Well we're looking to mirror lubridate's epiyear for our R implementation, see ARROW-14824.
We could also call it us_epiyear to preventively disambiguate.

[lidavidm]

us_epiyear makes sense.

[rok]

@lidavidm Switched to us_epiyear.

[lidavidm]

Ah, the function doc description needs to be line-wrapped.

[rok]

Fixed.

[jorisvandenbossche]

Should there then also be an equivalent epiweek kernel?

[rok]

@jorisvandenbossche we currently have us_week and iso_week. us_week is us_epiyear-like. We kind of have two camps here - iso and us/epi. Very much open to suggestions on naming here.

[jorisvandenbossche]

OK, I see. For consistency with us_week, could then also call it us_year? Or is that too vague?

[rok]

I don't mind either way. US year seems good because it's consistent with the ISO year definition - year starts with week 1 and it's either from Monday (ISO) for Sunday (US). On the other hand it is inventing a new name :).

[jorisvandenbossche]

The "us_week" was also a new invented name at the time? (or is that used elsewhere)

[rok]

The "us_week" was also a new invented name at the time? (or is that used elsewhere)

So was assume_timezone. I suppose we've crossed that threshold. I'll change to us_year.

[rok]

@jorisvandenbossche done.

[ursabot]

Benchmark runs are scheduled for baseline = cce55b4 and contender = 54f6c03. 54f6c03 is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Finished ⬇️0.0% ⬆️0.0%] ec2-t3-xlarge-us-east-2
[Finished ⬇️2.56% ⬆️0.0%] test-mac-arm
[Failed ⬇️0.71% ⬆️0.0%] ursa-i9-9960x
[Finished ⬇️0.43% ⬆️0.04%] ursa-thinkcentre-m75q
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python. Runs only benchmarks with cloud = True
test-mac-arm: Supported benchmark langs: C++, Python, R
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java

[rok]

Thanks @lidavidm @jorisvandenbossche !