cut,CFtime-method {CFtime} | R Documentation |
Create a factor for a CFtime instance
Description
Method for base::cut()
applied to CFtime objects.
Usage
## S4 method for signature 'CFtime'
cut(x, breaks, ...)
Arguments
x |
An instance of CFtime. |
breaks |
A character string of a factor period (see |
... |
Ignored. |
Details
When breaks
is one of "year", "season", "quarter", "month", "dekad", "day"
a factor is generated like by CFfactor()
.
When breaks
is a vector of character timestamps a factor is produced with a
level for every interval between timestamps. The last timestamp, therefore,
is only used to close the interval started by the pen-ultimate timestamp -
use a distant timestamp (e.g. range(x)[2]
) to ensure that all offsets to
the end of the CFtime time series are included, if so desired. The last
timestamp will become the upper bound in the CFtime instance that is returned
as an attribute to this function so a sensible value for the last timestamp
is advisable. The earliest timestamp cannot be earlier than the origin of the
datum of x
.
This method works similar to base::cut.POSIXt()
but there are some
differences in the arguments: for breaks
the set of options is different
and no preceding integer is allowed, labels
are always assigned using
values of breaks
, and the interval is always left-closed.
Value
A factor with levels according to the breaks
argument, with
attributes 'period', 'epoch' and 'CFtime'. When breaks
is a factor
period, attribute 'period' has that value, otherwise it is '"day"'. When
breaks
is a character vector of timestamps, attribute 'CFtime' holds an
instance of CFtime that has the same definition as x
, but with (ordered)
offsets generated from the breaks
. Attribute 'epoch' is always -1.
See Also
CFfactor()
produces a factor for several fixed periods, including
for epochs.
Examples
x <- CFtime("days since 2021-01-01", "365_day", 0:729)
breaks <- c("2022-02-01", "2021-12-01", "2023-01-01")
cut(x, breaks)