sub_holder {textclean}R Documentation

Hold the Place of Characters Prior to Subbing

Description

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

sub_holder(x, pattern, alpha.type = TRUE, ...)

Arguments

x

A character vector.

pattern

Character string to be matched in the given character vector.

alpha.type

logical. If TRUE alpha (lower case letters) are used for the key. If FALSE numbers are used as the key.

...

Additional arguments passed to gsub.

Value

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 'zzzplaceholder' followed by lower case letter keys followed by 'zzz'.

Examples

## `alpha.type` as TRUE
library(lexicon); library(textshape)
(fake_dat <- paste(hash_emoticons[1:11, 1, with=FALSE][[1]], DATA$state))
(m <- sub_holder(fake_dat, hash_emoticons[[1]]))
m$unhold(strip(m$output))

## `alpha.type` as FALSE (numeric keys)
vowels <- LETTERS[c(1, 5, 9, 15, 21)]
(m2 <- sub_holder(toupper(DATA$state), vowels, alpha.type = FALSE))
m2$unhold(gsub("[^0-9]", "", m2$output))
mtabulate(strsplit(m2$unhold(gsub("[^0-9]", "", m2$output)), ""))
[Package textclean version 0.7.2 Index]