stri_locate_boundaries: Locate Text Boundaries

Description

These functions locate text boundaries (like character, word, line, or sentence boundaries). Use stri_locate_all_* to locate all the matches. stri_locate_first_* and stri_locate_last_* give the first or the last matches, respectively.

Usage

stri_locate_all_boundaries(
  str,
  omit_no_match = FALSE,
  get_length = FALSE,
  ...,
  opts_brkiter = NULL
)

stri_locate_last_boundaries(str, get_length = FALSE, ..., opts_brkiter = NULL)

stri_locate_first_boundaries(str, get_length = FALSE, ..., opts_brkiter = NULL)

stri_locate_all_words(
  str,
  omit_no_match = FALSE,
  locale = NULL,
  get_length = FALSE
)

stri_locate_last_words(str, locale = NULL, get_length = FALSE)

stri_locate_first_words(str, locale = NULL, get_length = FALSE)

Arguments

str	character vector or an object coercible to
omit_no_match	single logical value; if TRUE, a no-match will be indicated by a matrix with 0 rows stri_locate_all_* only
get_length	single logical value; if FALSE (default), generate from-to matrices; otherwise, output from-length ones
...	additional settings for opts_brkiter
opts_brkiter	named list with ICU BreakIterator’s settings, see stri_opts_brkiter; NULL for default break iterator, i.e., line_break
locale	NULL or '' for text boundary analysis following the conventions of the default locale, or a single string with locale identifier, see stringi-locale

Details

Vectorized over str.

For more information on text boundary analysis performed by ICU’s BreakIterator, see stringi-search-boundaries.

For stri_locate_*_words, just like in stri_extract_all_words and stri_count_words, ICU’s word BreakIterator iterator is used to locate the word boundaries, and all non-word characters (UBRK_WORD_NONE rule status) are ignored. This function is equivalent to a call to stri_locate_*_boundaries(str, type='word', skip_word_none=TRUE, locale=locale)

Value

stri_locate_all_* yields a list of length(str) integer matrices. stri_locate_first_* and stri_locate_last_* generate return an integer matrix. See stri_locate for more details.

Author(s)

Marek Gagolewski and other contributors

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 search_locate: about_search, stri_locate_all()

Other indexing: stri_locate_all(), stri_sub(), stri_sub_all()

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_opts_collator(), stri_order(), stri_rank(), stri_sort(), stri_sort_key(), stri_split_boundaries(), stri_trans_tolower(), stri_unique(), stri_wrap()

Other text_boundaries: about_search, about_search_boundaries, stri_count_boundaries(), stri_extract_all_boundaries(), stri_opts_brkiter(), stri_split_boundaries(), stri_split_lines(), stri_trans_tolower(), stri_wrap()

Examples

test <- 'The\u00a0above-mentioned    features are very useful. Spam, spam, eggs, bacon, and spam.'
stri_locate_all_words(test)
## [[1]]
##       start end
##  [1,]     1   3
##  [2,]     5   9
##  [3,]    11  19
##  [4,]    24  31
##  [5,]    33  35
##  [6,]    37  40
##  [7,]    42  47
##  [8,]    50  53
##  [9,]    56  59
## [10,]    62  65
## [11,]    68  72
## [12,]    75  77
## [13,]    79  82
stri_locate_all_boundaries(
    'Mr. Jones and Mrs. Brown are very happy. So am I, Prof. Smith.',
    type='sentence',
    locale='en_US@ss=standard' # ICU >= 56 only
)
## [[1]]
##      start end
## [1,]     1  41
## [2,]    42  62