rm_tag function

Remove/Replace/Extract Person Tags

Remove/replace/extract person tags from a string.

rm_tag(
  text.var,
  trim = !extract,
  clean = TRUE,
  pattern = "@rm_tag",
  replacement = "",
  extract = FALSE,
  dictionary = getOption("regex.library"),
  ...
)

ex_tag(
  text.var,
  trim = !extract,
  clean = TRUE,
  pattern = "@rm_tag",
  replacement = "",
  extract = TRUE,
  dictionary = getOption("regex.library"),
  ...
)

Arguments

• text.var: The text variable.
• trim: logical. If TRUE removes leading and trailing white spaces.
• clean: trim logical. If TRUE extra white spaces and escaped character will be removed.
• pattern: A character string containing a regular expression (or character string for fixed = TRUE) to be matched in the given character vector. Default, @rm_tag uses the rm_tag regex from the regular expression dictionary from the dictionary argument.
• replacement: Replacement for matched pattern.
• extract: logical. If TRUE the person tags are extracted into a list of vectors.
• dictionary: A dictionary of canned regular expressions to search within if pattern begins with "@rm_".
• ...: Other arguments passed to gsub.

Returns

Returns a character string with person tags removed.

Details

The default regex pattern "(?<![@\w])@([a-z0-9_]+)\b" is more liberal and searches for the at (@) symbol followed by any word. This can be accessed via pattern = "@rm_tag". Twitter user names are more constrained. A second regex ("(?<![@\w])@([a-z0-9_]{1,15})\b") is provide that contains the latter word to substring that begins with an at (@) followed by a word composed of alpha-numeric characters and underscores, no longer than 15 characters. This can be accessed via pattern = "@rm_tag2" (see Examples ).

Examples

x <- c("@hadley I like #rstats for #ggplot2 work.",
    "Difference between #magrittr and #pipeR, both implement pipeline operators for #rstats:
        http://renkun.me/r/2014/07/26/difference-between-magrittr-and-pipeR.html @timelyportfolio",
    "Slides from great talk: @ramnath_vaidya: Interactive slides from Interactive Visualization
        presentation #user2014. http://ramnathv.github.io/user2014-rcharts/#1",
    "tyler.rinker@gamil.com is my email", 
    "A non valid Twitter is @abcdefghijklmnopqrstuvwxyz"
)

rm_tag(x)
rm_tag(rm_hash(x))
ex_tag(x)

## more restrictive Twitter regex
ex_tag(x, pattern="@rm_tag2") 

## Remove only the @ sign
rm_tag(x, replacement = "\\3")
rm_tag(x, replacement = "\\3", pattern="@rm_tag2")

See Also

gsub, stri_extract_all_regex

Other rm_ functions: rm_abbreviation(), rm_between(), rm_bracket(), rm_caps(), rm_caps_phrase(), rm_citation(), rm_citation_tex(), rm_city_state(), rm_city_state_zip(), rm_date(), rm_default(), rm_dollar(), rm_email(), rm_emoticon(), rm_endmark(), rm_hash(), rm_nchar_words(), rm_non_ascii(), rm_non_words(), rm_number(), rm_percent(), rm_phone(), rm_postal_code(), rm_repeated_characters(), rm_repeated_phrases(), rm_repeated_words(), rm_time(), rm_title_name(), rm_url(), rm_white(), rm_zip()