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<table width="100%" summary="page for stri_replace_all {stringi}"><tr><td>stri_replace_all {stringi}</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Replace Occurrences of a Pattern</h2>

<h3>Description</h3>

<p>These functions replace, with the given replacement string, every/first/last
substring of the input that matches the specified <code>pattern</code>.
</p>

<h3>Usage</h3>

<pre>
stri_replace_all(str, replacement, ..., regex, fixed, coll, charclass)

stri_replace_first(str, replacement, ..., regex, fixed, coll, charclass)

stri_replace_last(str, replacement, ..., regex, fixed, coll, charclass)

stri_replace(
  str,
  replacement,
  ...,
  regex,
  fixed,
  coll,
  charclass,
  mode = c("first", "all", "last")
)

stri_replace_all_charclass(
  str,
  pattern,
  replacement,
  merge = FALSE,
  vectorize_all = TRUE
)

stri_replace_first_charclass(str, pattern, replacement)

stri_replace_last_charclass(str, pattern, replacement)

stri_replace_all_coll(
  str,
  pattern,
  replacement,
  vectorize_all = TRUE,
  ...,
  opts_collator = NULL
)

stri_replace_first_coll(str, pattern, replacement, ..., opts_collator = NULL)

stri_replace_last_coll(str, pattern, replacement, ..., opts_collator = NULL)

stri_replace_all_fixed(
  str,
  pattern,
  replacement,
  vectorize_all = TRUE,
  ...,
  opts_fixed = NULL
)

stri_replace_first_fixed(str, pattern, replacement, ..., opts_fixed = NULL)

stri_replace_last_fixed(str, pattern, replacement, ..., opts_fixed = NULL)

stri_replace_all_regex(
  str,
  pattern,
  replacement,
  vectorize_all = TRUE,
  ...,
  opts_regex = NULL
)

stri_replace_first_regex(str, pattern, replacement, ..., opts_regex = NULL)

stri_replace_last_regex(str, pattern, replacement, ..., opts_regex = NULL)
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>str</code></td>
<td>
<p>character vector; strings to search in</p>
</td></tr>
<tr valign="top"><td><code>replacement</code></td>
<td>
<p>character vector with replacements for matched patterns</p>
</td></tr>
<tr valign="top"><td><code>...</code></td>
<td>
<p>supplementary arguments passed to the underlying functions,
including additional settings for <code>opts_collator</code>, <code>opts_regex</code>,
<code>opts_fixed</code>, and so on</p>
</td></tr>
<tr valign="top"><td><code>mode</code></td>
<td>
<p>single string;
one of: <code>"first"</code> (the default), <code>"all"</code>, <code>"last"</code></p>
</td></tr>
<tr valign="top"><td><code>pattern, regex, fixed, coll, charclass</code></td>
<td>
<p>character vector;
search patterns; for more details refer to <a href="stringi-search.html">stringi-search</a></p>
</td></tr>
<tr valign="top"><td><code>merge</code></td>
<td>
<p>single logical value;
should consecutive matches be merged into one string;
<code>stri_replace_all_charclass</code> only</p>
</td></tr>
<tr valign="top"><td><code>vectorize_all</code></td>
<td>
<p>single logical value;
should each occurrence of a pattern in every string
be replaced by a corresponding replacement string?;
<code>stri_replace_all_*</code> only</p>
</td></tr>
<tr valign="top"><td><code>opts_collator, opts_fixed, opts_regex</code></td>
<td>
<p>a named list used to tune up
the search engine's settings; see
<code><a href="stri_opts_collator.html">stri_opts_collator</a></code>, <code><a href="stri_opts_fixed.html">stri_opts_fixed</a></code>,
and <code><a href="stri_opts_regex.html">stri_opts_regex</a></code>, respectively; <code>NULL</code>
for the defaults</p>
</td></tr>
</table>

<h3>Details</h3>

<p>By default, all the functions are vectorized over
<code>str</code>, <code>pattern</code>, <code>replacement</code> (with recycling
of the elements in the shorter vector if necessary).
Input that is not part of any match is left unchanged;
each match is replaced in the result by the replacement string.
</p>
<p>However, for <code>stri_replace_all*</code>, if <code>vectorize_all</code> is <code>FALSE</code>,
the each substring matching any of the supplied <code>pattern</code>s
is replaced by a corresponding <code>replacement</code> string.
In such a case, the vectorization is over <code>str</code>,
and - independently - over <code>pattern</code> and <code>replacement</code>.
In other words, this is equivalent to something like
<code>for (i in 1:npatterns) str &lt;- stri_replace_all(str, pattern[i], replacement[i]</code>.
Note that you must set <code>length(pattern) &gt;= length(replacement)</code>.
</p>
<p>In case of <code>stri_replace_*_regex</code>,
the replacement string may contain references to capture groups
(in round parentheses).
References are of the form <code>$n</code>, where <code>n</code> is the number
of the capture group (<code>$1</code> denotes the first group).
For the literal <code>$</code>,
escape it with a backslash.
Moreover, <code>${name}</code> are used for named capture groups.
</p>
<p><code>stri_replace</code>, <code>stri_replace_all</code>, <code>stri_replace_first</code>,
and <code>stri_replace_last</code> are convenience functions; they just call
<code>stri_replace_*_*</code> variants, depending on the arguments used.
</p>
<p>If you wish to remove white-spaces from the start or end
of a string, see <code><a href="stri_trim.html">stri_trim</a></code>.
</p>

<h3>Value</h3>

<p>All the functions return a character vector.
</p>

<p>Other search_replace: 
<code><a href="stri_trim.html">stri_trim_both</a>()</code>,
<code><a href="stringi-search.html">stringi-search</a></code>
</p>

<h3>Examples</h3>

<pre>
stri_replace_all_charclass("aaaa", "[a]", "b", merge=c(TRUE, FALSE))

stri_replace_all_charclass("a\nb\tc   d", "\\p{WHITE_SPACE}", " ")
stri_replace_all_charclass("a\nb\tc   d", "\\p{WHITE_SPACE}", " ", merge=TRUE)

s &lt;- "Lorem ipsum dolor sit amet, consectetur adipisicing elit."
stri_replace_all_fixed(s, " ", "#")
stri_replace_all_fixed(s, "o", "0")

stri_replace_all_fixed(c("1", "NULL", "3"), "NULL", NA)

stri_replace_all_regex(s, " .*? ", "#")
stri_replace_all_regex(s, "(el|s)it", "1234")
stri_replace_all_regex('abaca', 'a', c('!', '*'))
stri_replace_all_regex('123|456|789', '(\\p{N}).(\\p{N})', '$2-$1')
stri_replace_all_regex(c("stringi R", "REXAMINE", "123"), '( R|R.)', ' r ')

## Not run: 
# named capture groups available since ICU 55
stri_replace_all_regex("words 123 and numbers 456",
   "(?&lt;numbers&gt;[0-9]+)", "!${numbers}!")

## End(Not run)

# Compare the results:
stri_replace_all_fixed("The quick brown fox jumped over the lazy dog.",
     c("quick", "brown", "fox"), c("slow",  "black", "bear"), vectorize_all=TRUE)
stri_replace_all_fixed("The quick brown fox jumped over the lazy dog.",
     c("quick", "brown", "fox"), c("slow",  "black", "bear"), vectorize_all=FALSE)

# Compare the results:
stri_replace_all_fixed("The quicker brown fox jumped over the lazy dog.",
     c("quick", "brown", "fox"), c("slow",  "black", "bear"), vectorize_all=FALSE)
stri_replace_all_regex("The quicker brown fox jumped over the lazy dog.",
     "\\b"%s+%c("quick", "brown", "fox")%s+%"\\b", c("slow",  "black", "bear"), vectorize_all=FALSE)

</pre>

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