width
.
stri_wrap(str, width = floor(0.9 * getOption("width")), cost_exponent = 2, simplify = TRUE, normalize = TRUE, indent = 0, exdent = 0, prefix = "", initial = prefix, whitespace_only = FALSE, use_length = FALSE, locale = NULL)
prefix
is used as prefix for each
line except the first, for which initial
is utilizedFALSE
, ICU's line break iterator is used to split text
into words, which is suitable for natural language processingstri_width
)?NULL
or ""
for text boundary analysis following
the conventions of the default locale, or a single string with
locale identifier, see stringi-localesimplify
is TRUE
, then a character vector is returned.
Otherwise, you will get a list of length(str)
character vectors.
str
.If whitespace_only
is FALSE
,
then ICU's line-BreakIterator
is used to determine
text boundaries at which a line break is possible.
This is a locale-dependent operation.
Otherwise, the breaks are only at whitespaces.
Note that Unicode code points may have various widths when
printed on the console and that the function takes that by default
into account. By changing the state of the use_length
argument, this function starts to act like each code point
was of width 1. This feature should rather be used with
text in Latin script.
If normalize
is FALSE
,
then multiple white spaces between the word boundaries are
preserved within each wrapped line.
In such a case, none of the strings can contain \r
, \n
,
or other new line characters, otherwise you will get at error.
You should split the input text into lines
or e.g. substitute line breaks with spaces
before applying this function.
On the other hand, if normalize
is TRUE
, then
all consecutive white space (ASCII space, horizontal TAB, CR, LF)
sequences are replaced with single ASCII spaces
before actual string wrapping. Moreover, stri_split_lines
and stri_trans_nfc
is called on the input character vector.
This is for compatibility with strwrap
.
The greedy algorithm (for cost_exponent
being non-positive)
provides a very simple way for word wrapping.
It always puts as many words in each line as possible.
This method -- contrary to the dynamic algorithm -- does not minimize
the number of space left at the end of every line.
The dynamic algorithm (a.k.a. Knuth's word wrapping algorithm)
is more complex, but it returns text wrapped
in a more aesthetic way. This method minimizes the squared
(by default, see cost_exponent
) number of spaces (raggedness)
at the end of each line, so the text is mode arranged evenly.
Note that the cost of printing the last line is always zero.
%s<%< a="">%<>
,
stri_compare
,
stri_count_boundaries
,
stri_duplicated
,
stri_enc_detect2
,
stri_extract_all_boundaries
,
stri_locate_all_boundaries
,
stri_opts_collator
,
stri_order
,
stri_split_boundaries
,
stri_trans_tolower
,
stri_unique
, stringi-locale
,
stringi-search-boundaries
,
stringi-search-coll
Other text_boundaries: stri_count_boundaries
,
stri_extract_all_boundaries
,
stri_locate_all_boundaries
,
stri_opts_brkiter
,
stri_split_boundaries
,
stri_split_lines
,
stri_trans_tolower
,
stringi-search-boundaries
,
stringi-search
s <- stri_paste(
"Lorem ipsum dolor sit amet, consectetur adipisicing elit. Proin ",
"nibh augue, suscipit a, scelerisque sed, lacinia in, mi. Cras vel ",
"lorem. Etiam pellentesque aliquet tellus.")
cat(stri_wrap(s, 20, 0.0), sep="\n") # greedy
cat(stri_wrap(s, 20, 2.0), sep="\n") # dynamic
cat(stri_pad(stri_wrap(s), side='both'), sep="\n")
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