rm_date function

Remove/Replace/Extract Dates

Remove/replace/extract dates from a string in the form of (1) XX/XX/XXXX, XX/XX/XX, XX-XX-XXXX, XX-XX-XX, XX.XX.XXXX, or XX.XX.XX OR (2) March XX, XXXX or Mar XX, XXXX OR (3) both forms.

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

ex_date(
  text.var,
  trim = !extract,
  clean = TRUE,
  pattern = "@rm_date",
  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 (see Details for additional information). Default, @rm_date uses the rm_date regex from the regular expression dictionary from the dictionary argument.
• replacement: Replacement for matched pattern.
• extract: logical. If TRUE the dates 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 dates removed.

Details

The default regular expression used by rm_date finds numeric representations not word/abbreviations. This means that "June 13, 2002" is not matched. This behavior can be altered (to include month names/abbreviations) by using a secondary regular expression from the regex_usa data (or other dictionary) via (pattern = "@rm_date2", pattern = "@rm_date3", or pattern = "@rm_date4"). See Examples for example usage.

Examples

## Numeric Date Representation
x <- paste0("Format dates as 04/12/2014, 04-12-2014, 04.12.2014. or",
    " 04/12/14 but leaves mismatched: 12.12/2014")
rm_date(x)
ex_date(x)

## Word/Abbreviation Date Representation
x2 <- paste0("Format dates as Sept 09, 2002 or October 22, 1887",
  "but not 04-12-2014 and may match good 00, 9999")
rm_date(x2, pattern="@rm_date2")
ex_date(x2, pattern="@rm_date2")

## Year-Month-Day Representation
x3 <- sprintf("R uses time in this format %s.", Sys.time())
rm_date(x3, pattern="@rm_date3")

## Grab all types
ex_date(c(x, x2, x3), pattern="@rm_date4")

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_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_tag(), rm_time(), rm_title_name(), rm_url(), rm_white(), rm_zip()