R: Compute the exact length of a time span

time_length {lubridate} | R Documentation

## Compute the exact length of a time span

### Description

Compute the exact length of a time span

### Usage

    time_length(x, unit = "second")

    ## S4 method for signature 'Interval'
    time_length(x, unit = "second")

### Arguments

`x` | a duration, period, difftime or interval
`unit` | a character string that specifies with time units to use

### Details

When `x` is an Interval object and `unit` are years or months, `time_length()` takes into account the fact that all months and years don't have the same number of days.

When `x` is a Duration, Period or `difftime()` object, length in months or years is based on their most common lengths in seconds (see `timespan()`).

### Value

the length of the interval in the specified unit. A negative number connotes a negative interval or duration

### See Also

`timespan()`

### Examples

    int <- interval(ymd("1980-01-01"), ymd("2014-09-18"))
    time_length(int, "week")

    # Exact age
    time_length(int, "year")

    # Age at last anniversary
    trunc(time_length(int, "year"))

    # Example of difference between intervals and durations
    int <- interval(ymd("1900-01-01"), ymd("1999-12-31"))
    time_length(int, "year")
    time_length(as.duration(int), "year")

[Package lubridate version 1.7.2 Index]