Convert UTC Referenced Dates Into Temporal Amounts
Convert a UTC referenced date into a temporal amount.
utinvcal.nc(unitstring, value)
unitstring |
A temporal unit with an origin (e.g., “days since 1900-01-01”). |
value |
Dates to convert as a numeric vector or array, or a vector of strings or POSIXct values. |
Uses the UDUNITS library to convert a UTC-referenced date and time into the amount, value, of the temporal unit, unitstring.
If the dates are given in string form, the structure must be exactly "YYYY-MM-DD hh:mm:ss".
A vector of POSIXct values is also accepted as input. These are converted to the specified units by a linear transformation, without an intermediate separation into date components.
A vector containing the amount(s) of the temporal unit(s) corresponding to the given date(s).
Pavel Michna, Milton Woods
if (inherits(try(utcal.nc("seconds since 1970-01-01", 0)), "try-error")) {
warning("UDUNITS calendar conversions not supported by this build of RNetCDF")
} else {
## Convert UTC referenced time to other time units
utinvcal.nc("hours since 1900-01-01 00:00:00 +01:00", c(1900,1,1,5,25,0))
utinvcal.nc("hours since 1900-01-01 00:00:00 +01:00", "1900-01-01 05:25:00")
utinvcal.nc("hours since 1900-01-01 00:00:00 +01:00", ISOdatetime(1900,1,1,5,25,0,tz="UTC"))
}
## An example of reading and writing a netcdf time coordinate
## is given in the help for utcal.ncPlease choose more modern alternatives, such as Google Chrome or Mozilla Firefox.