The data are from https://www.timeanddate.com/library/abbreviations/timezones/ and were hand-edited to develop this code, so there may be errors. Also, note that some of these contradict; if you examine the code, you'll see some commented-out portions that represent solving conflicting definitions by choosing the more common timezone abbreviation over a the less common one.

GMTOffsetFromTz(tz)

## Arguments

tz a timezone, e.g. UTC.

## Value

Number of hours in offset, e.g. AST yields 4.

## Examples

library(oce)
cat("Atlantic Standard Time is ", GMTOffsetFromTz("AST"), "hours after UTC")#> Atlantic Standard Time is  4 hours after UTC