multigsub: Multiple gsub

In trinker/qdap: Bridging the Gap Between Qualitative Data and Quantitative Analysis

Description

multigsub - A wrapper for gsub that takes a vector of search terms and a vector or single value of replacements.

sub_holder - This function holds the place for particular character values, allowing the user to manipulate the vector and then revert the place holders back to the original values.

Usage

multigsub(
  pattern,
  replacement,
  text.var,
  leadspace = FALSE,
  trailspace = FALSE,
  fixed = TRUE,
  trim = TRUE,
  order.pattern = fixed,
  ...
)

mgsub(
  pattern,
  replacement,
  text.var,
  leadspace = FALSE,
  trailspace = FALSE,
  fixed = TRUE,
  trim = TRUE,
  order.pattern = fixed,
  ...
)

sub_holder(pattern, text.var, alpha.type = TRUE, ...)

Arguments

pattern	Character string to be matched in the given character vector.
replacement	Character string equal in length to pattern or of length one which are a replacement for matched pattern.
text.var	The text variable.
leadspace	logical. If TRUE inserts a leading space in the replacements.
trailspace	logical. If TRUE inserts a trailing space in the replacements.
fixed	logical. If TRUE, pattern is a string to be matched as is. Overrides all conflicting arguments.
trim	logical. If TRUE leading and trailing white spaces are removed and multiple white spaces are reduced to a single white space.
order.pattern	logical. If TRUE and fixed = TRUE, the pattern string is sorted by number of characters to prevent substrings replacing meta strings (e.g., pattern = c("the", "then") resorts to search for "then" first).
...	Additional arguments passed to gsub.
alpha.type	logical. If TRUE alpha (lower case letters) are used for the key. If FALSE numbers are used as the key.

Value

multigsub - Returns a vector with the pattern replaced.

sub_holder - Returns a list with the following:

output	keyed place holder character vector
unhold	A function used to revert back to the original values

Note

The unhold function for sub_holder will only work on keys that have not been disturbed by subsequent alterations. The key follows the pattern of 'qdapplaceholder' followed by lower case letter keys followed by 'qdap'.

See Also

gsub

Examples

## Not run: 
## ======================
##    `mgsub` Function
## ======================

multigsub(c("it's", "I'm"), c("it is", "I am"), DATA$state)
mgsub(c("it's", "I'm"), c("it is", "I am"), DATA$state)
mgsub("[[:punct:]]", "PUNC", DATA$state, fixed = FALSE)

## ====================== 
## `sub_holder` Function
## ======================

## `alpha.type` as TRUE
(fake_dat <- paste(emoticon[1:11,2], DATA$state))
(m <- sub_holder(emoticon[,2], fake_dat))
m$unhold(strip(m$output))
# With Stemming
m$unhold(stemmer(strip(m$output), capitalize = FALSE))

## `alpha.type` as FALSE (numeric keys)
vowels <- LETTERS[c(1, 5, 9, 15, 21)]
(m2 <- sub_holder(vowels, toupper(DATA$state), alpha.type = FALSE))
m2$unhold(gsub("[^0-9]", "", m2$output))
mtabulate(strsplit(m2$unhold(gsub("[^0-9]", "", m2$output)), ""))

## End(Not run)

trinker/qdap documentation built on Sept. 30, 2020, 6:28 p.m.