Should has nothing to do with it. That is the way the Olsen tz database works.
See en.wikipedia.org/wiki/Tz_database.
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Sent from my phone. Please excuse my brevity.
Andrew Digby <andrewdigby at mac.com> wrote:
>
>I'm struggling with time zone version when expressed as hours offset
>from GMT. Can anyone confirm that the behaviour below is incorrect? It
>seems that the GMT offsets are backwards:
>
>> format(as.POSIXct("2011-05-23 17:23:00",
>tz="Europe/London"),tz="America/New_York",usetz=T)
>[1] "2011-05-23 12:23:00 EDT"
>
>- this works.
>
>> format(as.POSIXct("2011-05-23
17:23:00",tz="GMT"),tz="GMT-5",usetz=T)
>[1] "2011-05-23 22:23:00 GMT"
>
>- this doesn't work: 17:23:00 GMT should be 12:23:00 GMT-5!
>
>
>Thanks.
>
>
>R version 2.13.0 (2011-04-13)
>Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit)
>
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