% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/api.R
\name{cut.CFTime}
\alias{cut.CFTime}
\alias{cut}
\title{Create a factor for a \code{CFTime} instance}
\usage{
\method{cut}{CFTime}(x, breaks, ...)
}
\arguments{
\item{x}{An instance of \code{CFTime}.}

\item{breaks}{A character string of a factor period (see \code{\link[=CFfactor]{CFfactor()}} for a
description), or a character vector of timestamps that conform to the
calendar of \code{x}, with a length of at least 2. Timestamps must be given in
ISO8601 format, e.g. "2024-04-10 21:31:43".}

\item{...}{Ignored.}
}
\value{
A factor with levels according to the \code{breaks} argument, with
attributes 'period', 'era' and 'CFTime'. When \code{breaks} is a factor
period, attribute 'period' has that value, otherwise it is '"day"'. When
\code{breaks} is a character vector of timestamps, attribute 'CFTime' holds an
instance of \code{CFTime} that has the same definition as \code{x}, but with (ordered)
offsets generated from the \code{breaks}. Attribute 'era' is always -1.
}
\description{
Method for \code{\link[base:cut]{base::cut()}} applied to \link{CFTime} objects.
}
\details{
When \code{breaks} is one of \verb{"year", "season", "quarter", "month", "dekad", "day"} a factor is generated like by \code{\link[=CFfactor]{CFfactor()}}.

When \code{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. \code{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 \code{CFTime} instance that is
returned as an attribute to this function so a sensible value for the last
timestamp is advisable.

This method works similar to \code{\link[base:cut.POSIXt]{base::cut.POSIXt()}} but there are some
differences in the arguments: for \code{breaks} the set of options is different
and no preceding integer is allowed, \code{labels} are always assigned using
values of \code{breaks}, and the interval is always left-closed.
}
\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)
}
\seealso{
\code{\link[=CFfactor]{CFfactor()}} produces a factor for several fixed periods, including
for eras.
}
