R: Sampling Times of Time Series

time {stats} | R Documentation

## Sampling Times of Time Series

### Description

`time` creates the vector of times at which a time series was sampled.

`cycle` gives the positions in the cycle of each observation.

`frequency` returns the number of samples per unit time and `deltat` the time interval between observations (see `ts`).

### Usage

    time(x, ...)
    ## Default S3 method:
    time(x, offset = 0, ...)

    cycle(x, ...)
    frequency(x, ...)
    deltat(x, ...)

### Arguments

`x` | a univariate or multivariate time-series, or a vector or matrix.
`offset` | can be used to indicate when sampling took place in the time unit. `0` (the default) indicates the start of the unit, `0.5` the middle and `1` the end of the interval.
`...` | extra arguments for future methods.

### Details

These are all generic functions, which will use the `tsp` attribute of `x` if it exists. `time` and `cycle` have methods for class `ts` that coerce the result to that class.

### References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.

### See Also

`ts`, `start`, `tsp`, `window`.

`date` for clock time, `system.time` for CPU usage.

### Examples

    require(graphics)

    cycle(presidents)
    # a simple series plot
    plot(as.vector(time(presidents)), as.vector(presidents), type = "l")

[Package stats version 3.1.2 Index]