Hide navigation sidebar
Hide table of contents sidebar
Back to top
Edit this page
Toggle table of contents sidebar

# stri_order: Ordering Permutation

## Description

This function finds a permutation which rearranges the strings in a given character vector into the ascending or descending locale-dependent lexicographic order.

## Usage

    stri_order(str, decreasing = FALSE, na_last = TRUE, ..., opts_collator = NULL)

## Arguments

`str` | a character vector
`decreasing` | a single logical value; should the sort order be nondecreasing (`FALSE`, default) or nonincreasing (`TRUE`)?
`na_last` | a single logical value; controls the treatment of `NA`s in `str`. If `TRUE`, then missing values in `str` are put at the end; if `FALSE`, they are put at the beginning; if `NA`, then they are removed from the output
`...` | additional settings for `opts_collator`
`opts_collator` | a named list with ICU Collator’s options, see `stri_opts_collator`, `NULL` for default collation options

## Details

For more information on ICU’s Collator and how to tune it up in stringi, refer to `stri_opts_collator`.

As usual in stringi, non-character inputs are coerced to strings, see an example below for a somewhat non-intuitive behavior of lexicographic sorting on numeric inputs.

This function uses a stable sort algorithm (STL’s `stable_sort`), which performs up to \(N*log^2(N)\) element comparisons, where \(N\) is the length of `str`.

For ordering with regards to multiple criteria (such as sorting data frames by more than 1 column), see `stri_rank`.

## Value

The function yields an integer vector that gives the sort order.

## Author(s)

Marek Gagolewski and other contributors

## References

Collation - ICU User Guide, https://unicode-org.github.io/icu/userguide/collation/

## See Also

The official online manual of stringi at https://stringi.gagolewski.com/

Gagolewski M., stringi: Fast and portable character string processing in R, Journal of Statistical Software 103(2), 2022, 1-59, doi:10.18637/jss.v103.i02

Other locale_sensitive: `%s<%()`, `about_locale`, `about_search_boundaries`, `about_search_coll`, `stri_compare()`, `stri_count_boundaries()`, `stri_duplicated()`, `stri_enc_detect2()`, `stri_extract_all_boundaries()`, `stri_locate_all_boundaries()`, `stri_opts_collator()`, `stri_rank()`, `stri_sort()`, `stri_sort_key()`, `stri_split_boundaries()`, `stri_trans_tolower()`, `stri_unique()`, `stri_wrap()`

## Examples

    stri_order(c('hladny', 'chladny'), locale='pl_PL')
    ## [1] 2 1
    stri_order(c('hladny', 'chladny'), locale='sk_SK')
    ## [1] 1 2
    stri_order(c(1, 100, 2, 101, 11, 10))  # lexicographic order
    ## [1] 1 6 2 4 5 3
    stri_order(c(1, 100, 2, 101, 11, 10), numeric=TRUE)  # OK for integers
    ## [1] 1 3 6 5 2 4
    stri_order(c(0.25, 0.5, 1, -1, -2, -3), numeric=TRUE)  # incorrect
    ## [1] 4 5 6 2 1 3