Closed calconnect-ci closed 4 years ago
In GitLab by @ronaldtse on Sep 6, 2018, 09:05
Thanks for bringing this up. Notice that this representation does not allow negative integers, and it is an intentional omission in ISO 8601-2 -- I wrote it but it was removed afterwards. This also applies to the "Century" time scale component; negative century is not allowed.
The reason for removal is the confusion it may cause in the AD/BC calendar year scale. 8601 adopts the astronomical year scale that allows a year 0. There is no "0" year in AD/BC, it's 1 AD followed by 1 BC. Therefore, in 8601, year "0" means "1 BC".
I am however inclined to allow negative values for these, but it is not straightforward.
Original text for negative decade:
4.4.6 Decade and decade duration
The decade is represented as follows extending 4.3.3: Explicit: decE(m) = [!][“-”][decE]
EXAMPLE: ‘-10U’ in date represents the time interval of Gregorian years -100 through -91.
When a negative decade represents a date, the negative value is to represent the number of decades prior to the Gregorian year 0, where the first decade before the Gregorian year 0, the Gregorian years -1 through -10, is represented by the integer value ‘-1’.
Here's the problem with expressing "the fifty years preceding 400BCE":
The only way to express this using this document (this expression cannot be expressed in normal 8601) is:
Let's discuss.
In GitLab by @ronaldtse on Sep 7, 2018, 01:47
Minor change to report: "J" is now decade.
See 6d9097cd067922ab0ba090adf25274bf58be818c
In GitLab by @ronaldtse on Sep 7, 2018, 09:17
Do you mean the representation of negative values with [C] and [Y]? Century suffers from the exact same problem as Decade. If we want to represent blocks of BC, we need to have a syntax that offsets the year 0.
In GitLab by @ribose-jeffreylau on Sep 7, 2018, 08:48
Created by: atlauren
I certainly appreciate the difficulty of representing negative time values. Normative reference to historical periods is certainly a problem in academia, whether those periods are relatively recent (sociological, political), medium (biological) or long term (geological, astronomical).
Including the possibility for a limited set of values seems helpful (only [C] and [Y], perhaps?), albeit imperfect.
I don't think negative values are required, but if it's intentionally omitted should there be a statement to that effect?
In GitLab by @ribose-jeffreylau on Sep 7, 2018, 11:13
Created by: atlauren
Aich. Yeah, there's no getting around that is there? Maybe your example "-449Y/-400Y" really is the only practical away to express this.
In GitLab by @ronaldtse on Sep 7, 2018, 11:22
The easy way is to provide an addition symbol for “Shift”.
For example, “-45J1YQ” where the coefficient of “Q” indicates shift of one year to the decade.
In GitLab by @ronaldtse on Sep 9, 2018, 02:05
Proposal for negative decade and century here.
This allows -45J1YV
to represent "the fifty years preceding 400BCE".
-45JB
for "450BCE to 400BCE" (-449/-400
), and -8CB
for "8th Century BC". This is merely a convenience feature.@atlauren what do you think?
In GitLab by @ribose-jeffreylau on Sep 9, 2018, 06:33
Created by: atlauren
@ronaldtse I dig it. Ship it.
In GitLab by @ronaldtse on Sep 9, 2018, 15:14
Thanks @atlauren ! 👍
In GitLab by @ronaldtse on Sep 11, 2018, 02:46
So the "V" syntax was rejected from 8601-2, but I'm still trying with the "B".
In GitLab by @ronaldtse on Sep 11, 2018, 05:49
Submitted the "B", but let's see what happens.
In GitLab by @ribose-jeffreylau on Sep 6, 2018, 08:07
Created by: atlauren
Examples should include indications to anticipated, albeit noncommon, representations.
'0U' (years 00-09 CE)
(How would one represent "the fifty years preceding 400BCE"?)