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.
stri_locate_all_boundaries(str, omit_no_match = FALSE, ...,
opts_brkiter = NULL)stri_locate_last_boundaries(str, ..., opts_brkiter = NULL)
stri_locate_first_boundaries(str, ..., opts_brkiter = NULL)
stri_locate_all_words(str, omit_no_match = FALSE, locale = NULL)
stri_locate_last_words(str, locale = NULL)
stri_locate_first_words(str, locale = NULL)
character vector or an object coercible to
single logical value; if FALSE,
then 2 missing values will indicate that there are no text boundaries
additional settings for opts_brkiter
a named list with ICU BreakIterator's settings,
see stri_opts_brkiter;
NULL for default break iterator, i.e., line_break
NULL or "" for text boundary analysis following
the conventions of the default locale, or a single string with
locale identifier, see stringi-locale
For stri_locate_all_*, a list of length(str) integer matrices
is returned. The first column gives the start positions
of substrings between located boundaries, and the second column gives
the end positions. The indexes are code point-based, thus
they may be passed, e.g., to stri_sub or stri_sub_all.
Note that you get two NAs in one row
if there is no match (and omit_no_match is FALSE)
or there are missing data in the input vector.
stri_locate_first_* and stri_locate_last_*,
return an integer matrix with
two columns, giving the start and end positions of the first
or the last matches, respectively, and two NAs if there is no match.
Vectorized over str.
For more information on text boundary analysis
performed by ICU's BreakIterator, see
stringi-search-boundaries.
In case of 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 is function is equivalent to a call to
stri_locate_*_boundaries(str, type="word", skip_word_none=TRUE, locale=locale)
Other search_locate: stri_locate_all,
stringi-search
Other indexing: stri_locate_all,
stri_sub_all, stri_sub
Other locale_sensitive: %s<%,
stri_compare,
stri_count_boundaries,
stri_duplicated,
stri_enc_detect2,
stri_extract_all_boundaries,
stri_opts_collator,
stri_order, stri_sort,
stri_split_boundaries,
stri_trans_tolower,
stri_unique, stri_wrap,
stringi-locale,
stringi-search-boundaries,
stringi-search-coll
Other text_boundaries: stri_count_boundaries,
stri_extract_all_boundaries,
stri_opts_brkiter,
stri_split_boundaries,
stri_split_lines,
stri_trans_tolower,
stri_wrap,
stringi-search-boundaries,
stringi-search
# NOT RUN {
test <- "The\u00a0above-mentioned features are very useful. Kudos to their developers."
stri_locate_all_boundaries(test, type="line")
stri_locate_all_boundaries(test, type="word")
stri_locate_all_boundaries(test, type="sentence")
stri_locate_all_boundaries(test, type="character")
stri_locate_all_words(test)
stri_extract_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
# }
Run the code above in your browser using DataLab