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qdapRegex (version 0.7.2)

rm_date: Remove/Replace/Extract Dates

Description

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.

Usage

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.

Value

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.

See Also

gsub, stri_extract_all_regex

Other rm_ functions: rm_abbreviation, rm_between, rm_bracket, rm_caps_phrase, rm_caps, rm_citation_tex, rm_citation, rm_city_state_zip, rm_city_state, 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

Examples

Run this code
# NOT RUN {
## 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")
# }

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