Indian Time zone history and choice of Kolkata as reference location
On 2019-07-24 08:45, Alois Treindl wrote:
In my humble opinion, I think the choice TZ made for India, by selecting Kolkata (formerly Calcutta) as the reference location, was not a good choice.
I can understand your point -- but it is definitely not applicable to tzdb data which is not meant to cover historical data: However, the database is not designed for and does not suffice for applications requiring accurate handling of all past times everywhere, as it would take far too much effort and guesswork to record all details of pre-1970 civil timekeeping. (from theory.html) On the contrary, the tzdb rules for selecting a representative location for a time zone are carefully constructed so as to avoid political or other extraneous implications as far as possible. Past experience shows that this is a very advantageous design. Michael Deckers.
Alois Treindl wrote:
TZ was conscious of that problem
By "TZ" I guess you mean me, since I contributed the Indian data. If my guess is correct, then this statement is mistaken. When I made that contribution decades ago, I was not aware of the problems of historical time in India. Also, Calcutta was listed as the largest city in India in the source I casually consulted (sorry, I don't remember what it was). Although Delhi is the largest city in India now, it's not clear that it would be worth the technical and political hassle to switch names at this point, just as it's not clear that it would be worth switching Europe/Rome to Europe/Milan. If this situation comes up again when adding future entries, the theory.html file does not currently suggest preferring locations whose pre-1970 timestamp history is more reliable. I'm not sure we should add anything like that, but if we do the suggestion would be low priority because pre-1970 timestamps are lower priority.
participants (3)
-
Alois Treindl -
Michael H Deckers -
Paul Eggert