| % File src/library/stats/man/time.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2007 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{time} |
| \alias{time} |
| \alias{cycle} |
| \alias{frequency} |
| \alias{deltat} |
| \alias{time.default} |
| %\alias{time.ts} |
| %\alias{cycle.default} |
| %\alias{cycle.ts} |
| %\alias{frequency.default} |
| %\alias{deltat.default} |
| \title{Sampling Times of Time Series} |
| \description{ |
| \code{time} creates the vector of times at which a time series was sampled. |
| |
| \code{cycle} gives the positions in the cycle of each observation. |
| |
| \code{frequency} returns the number of samples per unit time and |
| \code{deltat} the time interval between observations (see |
| \code{\link{ts}}). |
| } |
| \usage{ |
| time(x, \dots) |
| \method{time}{default}(x, offset = 0, \dots) |
| |
| cycle(x, \dots) |
| frequency(x, \dots) |
| deltat(x, \dots) |
| } |
| \arguments{ |
| \item{x}{a univariate or multivariate time-series, or a vector or matrix.} |
| \item{offset}{can be used to indicate when sampling took place |
| in the time unit. \code{0} (the default) indicates the start |
| of the unit, \code{0.5} the middle and \code{1} the end of |
| the interval.} |
| \item{\dots}{extra arguments for future methods.} |
| } |
| \details{ |
| These are all generic functions, which will use the |
| \code{\link{tsp}} attribute of \code{x} if it exists. \code{time} |
| and \code{cycle} have methods for class \code{\link{ts}} that coerce |
| the result to that class. |
| } |
| \seealso{ |
| \code{\link{ts}}, \code{\link{start}}, \code{\link{tsp}}, |
| \code{\link{window}}. |
| |
| \code{\link{date}} for clock time, \code{\link{system.time}} |
| for CPU usage. |
| } |
| \references{ |
| Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) |
| \emph{The New S Language}. |
| Wadsworth & Brooks/Cole. |
| } |
| \examples{ |
| require(graphics) |
| |
| cycle(presidents) |
| # a simple series plot |
| plot(as.vector(time(presidents)), as.vector(presidents), type = "l") |
| } |
| \keyword{ts} |