stri_unique: Extract Unique Elements
Description
This function returns a character vector like str, but with duplicate elements removed.
Usage
stri_unique(str, ..., opts_collator = NULL)
Arguments
|
a character vector |
|
additional settings for |
|
a named list with ICU Collator’s options, see |
Details
As usual in stringi, no attributes are copied. Unlike unique, this function tests for canonical equivalence of strings (and not whether the strings are just bytewise equal). Such an operation is locale-dependent. Hence, stri_unique is significantly slower (but much better suited for natural language processing) than its base R counterpart.
See also stri_duplicated for indicating non-unique elements.
Value
Returns a character vector.
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_order(), stri_rank(), stri_sort_key(), stri_sort(), stri_split_boundaries(), stri_trans_tolower(), stri_wrap()
Examples
# normalized and non-Unicode-normalized version of the same code point:
stri_unique(c('\u0105', stri_trans_nfkd('\u0105')))
## [1] "ą"
unique(c('\u0105', stri_trans_nfkd('\u0105')))
## [1] "ą" "ą"
stri_unique(c('gro\u00df', 'GROSS', 'Gro\u00df', 'Gross'), strength=1)
## [1] "groß"