R: Convert monthly or quarterly data to chron

yearmon {chron} | R Documentation

## Convert monthly or quarterly data to chron

### Description

These functions can be used to convert the times of `"ts"` series with `frequency` of 12 or 4 or objects of `"yearmon"` and `"yearqtr"` class, as defined in the "zoo" package, to `chron` dates.

### Usage

    ## S3 method for class 'yearmon'
    as.chron(x, frac = 0, holidays = FALSE, ...)
    ## S3 method for class 'yearqtr'
    as.chron(x, frac = 0, holidays = FALSE, ...)
    ## S3 method for class 'ts'
    as.chron(x, frac = 0, holidays = FALSE, ...)

### Arguments

`x` | an object of class `"yearmon"` or `"yearqtr"` or `"ts"` objects, or a numeric vector interpreted “in years” and fractions of years.
`frac` | Number between zero and one inclusive representing the fraction of the way through the month or quarter.
`holidays` | If `TRUE` or a vector of chron dates, indicated holidays and weekends are excluded so the return value will be a non-holiday weekday.
`...` | Other arguments passed to `chron`.

### Details

The `"yearmon"` and `"yearqtr"` classes are defined in package zoo. If `holidays` is `TRUE` or a vector of dates then the `is.holiday` function is used to determine whether days are holidays.

The method for ts objects converts the times corresponding to `time(x)` to chron. The ts series must have a frequency that is a divisor of 12.

### Value

Returns a `chron` object.

### See Also

`is.holiday`, `ts`

### Examples

    ## Monthly time series data.
    as.chron(AirPassengers)
    as.chron(time(AirPassengers))
    ## convert to first day of the month that is not a weekend or holiday
    as.chron(AirPassengers, frac = 0, holidays = TRUE)
    ## convert to last day of the month
    as.chron(AirPassengers, frac = 1)
    ## convert to last day of the month that is not a weekend or holiday
    as.chron(AirPassengers, frac = 1, holidays = TRUE)
    ## convert to last weekday of the month
    as.chron(AirPassengers, frac = 1, holidays = c())

    ## Quarterly time series data.
    as.chron(presidents)
    as.chron(time(presidents))

[Package chron version 2.3-53 Index]