stri_split_boundaries {stringi} | R Documentation

## Split a String at Specific Text Boundaries

### Description

This function locates specific text boundaries (like character, word, line, or sentence boundaries) and splits strings at the indicated positions.

### Usage

    stri_split_boundaries(str, n = -1L, tokens_only = FALSE, simplify = FALSE,
      ..., opts_brkiter = NULL)

### Arguments

`str` | character vector or an object coercible to
`n` | integer vector, maximal number of strings to return
`tokens_only` | single logical value; may affect the result if `n` is positive, see Details
`simplify` | single logical value; if `TRUE` or `NA`, then a character matrix is returned; otherwise (the default), a list of character vectors is given, see Value
`...` | additional settings for `opts_brkiter`
`opts_brkiter` | a named list with ICU BreakIterator's settings as generated with `stri_opts_brkiter`; `NULL` for the default break iterator, i.e. `line_break`

### Details

Vectorized over `str` and `n`.

If `n` is negative (default), then all pieces are extracted. Otherwise, if `tokens_only` is `FALSE` (this is the default, for compatibility with the stringr package), then `n-1` tokes are extracted (if possible) and the `n`-th string gives the (non-split) remainder (see Examples). On the other hand, if `tokens_only` is `TRUE`, then only full tokens (up to `n` pieces) are extracted.

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

### Value

If `simplify=FALSE` (the default), then the functions return a list of character vectors.

Otherwise, `stri_list2matrix` with `byrow=TRUE` and `n_min=n` arguments is called on the resulting object. In such a case, a character matrix with `length(str)` rows is returned. Note that `stri_list2matrix`'s `fill` argument is set to an empty string and `NA`, for `simplify` equal to `TRUE` and `NA`, respectively.

### See Also

Other locale_sensitive: `%s<%`, `stri_compare`, `stri_count_boundaries`, `stri_duplicated`, `stri_enc_detect2`, `stri_extract_all_boundaries`, `stri_locate_all_boundaries`, `stri_opts_collator`, `stri_order`, `stri_trans_tolower`, `stri_unique`, `stri_wrap`, `stringi-locale`, `stringi-search-boundaries`, `stringi-search-coll`

Other search_split: `stri_split_lines`, `stri_split`, `stringi-search`

Other text_boundaries: `stri_count_boundaries`, `stri_extract_all_boundaries`, `stri_locate_all_boundaries`, `stri_opts_brkiter`, `stri_split_lines`, `stri_trans_tolower`, `stri_wrap`, `stringi-search-boundaries`, `stringi-search`

### Examples

    test <- "The\u00a0above-mentioned    features are very useful. " %s+%
       "Warm thanks to their developers. 123 456 789"
    stri_split_boundaries(test, type="line")
    stri_split_boundaries(test, type="word")
    stri_split_boundaries(test, type="word", skip_word_none=TRUE)
    stri_split_boundaries(test, type="word", skip_word_none=TRUE, skip_word_letter=TRUE)
    stri_split_boundaries(test, type="word", skip_word_none=TRUE, skip_word_number=TRUE)
    stri_split_boundaries(test, type="sentence")
    stri_split_boundaries(test, type="sentence", skip_sentence_sep=TRUE)
    stri_split_boundaries(test, type="character")

    # filtered break iterator with the new ICU:
    stri_split_boundaries("Mr. Jones and Mrs. Brown are very happy.
    So am I, Prof. Smith.", type="sentence", locale="@ss=standard") # ICU >= 56 only

[Package stringi version 1.1.1 Index]