user-friendly time zone list
yoshito_umaoka at us.ibm.com
yoshito_umaoka at us.ibm.com
Tue Apr 20 15:28:32 UTC 2010
Unicode CLDR project is trying to provide "common name" and its
CLDR introduced a concept - meta zone. For exmaple, poeple in the US
recognize New York and Detroit are in a same zone "Eastern Time" or "ET".
So CLDR defines a "meta" zone called "America_Eastern" and several
US/Canada zones are mapped to this metazone. Below is the part of data
maintained by CLDR project -
And metazone "America_Eastern" define display names -
<standard>Eastern Standard Time</standard>
<daylight>Eastern Daylight Time</daylight>
These names are translated into various languages. For example, in French
<generic>heure de l’Est</generic>
<standard>heure normale de l’Est</standard>
<daylight>heure avancée de l’Est</daylight>
However, by the nature of zones in the tz database, such mappings are
historic. For example, "America/Indiana/Knox" is moving back and forth
between Estern Time and Central Time. See the data maintained by CLDR
project below -
<usesMetazone to="1991-10-27 07:00" mzone="America_Central"/>
<usesMetazone to="2006-04-02 07:00" from="1991-10-27 07:00"
<usesMetazone from="2006-04-02 07:00" mzone="America_Central"/>
As you can see, your suggestion might not work well. For example, you
would create a common name for above zone -
Central Time (Knox, Indiana)
But, it is not true between 1991 and 2006. Of course, you can use the
current mapping only. Even in this case, you still probably need to
construct a name from separated sources, not in a single text.
Anyway, CLDR has such data in XML format which can be consumed for your
Douglass Davis <ddavis at northcarolina.edu> wrote on 04/20/2010 10:38:20 AM:
> Hello All,
> I am attempting to find a user-friendly list of time zones for users to
> select their current time zone. It would have common names that
> timezones are referred to, such as Eastern Time (US and Canada), and/or
> city names. This list should map the text to a time zone name such as
> "America/New_York." It would also remove multiple listings for what the
> user thinks of as the same time zone. Does any one know of such a list?
> If not, I would like to create one.
> One thing that perhaps would help is if I could group many timezones by
> if they are implemented exactly the same way in 2010. This would make it
> easy to remove multiple listings for the "same" time zone. Also, if
> there are any time zones that are strictly there for historical
> purposes, I would like to not have them in the list.
> I will put this list in the public domain if any other application
> developers want to use it.
> Please let me know if you have any suggestions as far as where I could
> find this list, or how I could create it.
> Douglass Davis
> Applications Developer
> UNC - General Administration
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