[tz] Indian Time zone history and choice of Kolkata as reference location

Michael H Deckers michael.h.deckers at googlemail.com
Wed Jul 24 12:19:58 UTC 2019

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 
       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.

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