Chronological ordering of year vectors

Sorts a vector of years into earliest-to-latest or latest-to-earliest chronological order based on its era.

Usage

yr_sort(x, reverse = FALSE, ...)

Arguments

x

yr vector with era

reverse

Set FALSE (the default) for chronological order (earliest to latest) or TRUE for reverse chronological order (latest to earliest).

...

Other arguments passed to sort(); in particular use na.last to control NA handling.

Value

Sorted yr vector

Details

This is implemented as a prefixed function rather than an S3 sort() method for yrs to avoid surprises when numerical (i.e. not chronological) sorting is expected.

See also

Other functions for chronological ordering and extremes: yr_extremes

Examples

# Forward-counting era:
x <- yr(c(200, 100, 300), "CE")
yr_sort(x)
#> # CE years <yr[3]>:
#> [1] 100 200 300
#> # Era: Common Era (CE): Gregorian years (365.2425 days), counted forwards from 0
yr_sort(x, reverse = TRUE)
#> # CE years <yr[3]>:
#> [1] 300 200 100
#> # Era: Common Era (CE): Gregorian years (365.2425 days), counted forwards from 0

# Backward-counting era:
y <- yr(c(200, 100, 300), "BCE")
yr_sort(y)
#> # BCE years <yr[3]>:
#> [1] 300 200 100
#> # Era: Before Common Era (BCE): Gregorian years (365.2425 days), counted backwards from 1
yr_sort(y, reverse = TRUE)
#> # BCE years <yr[3]>:
#> [1] 100 200 300
#> # Era: Before Common Era (BCE): Gregorian years (365.2425 days), counted backwards from 1