What is an alternative to passing a variable to a regular expression in R?

r, regex, variables

Solution

Use `paste` to concatenate the strings to create the pattern:

removeByLength<- function(text,lowerCutOff=2,upperCutOff=12){
  pattern <- paste("\\b[a-zA-Z0-9]{1,",lowerCutOff,
                 "}\\b|\\b[a-zA-Z0-9]{",upperCutOff,",}\\b", sep="")
  text <- gsub(pattern, " ", text)
  return(text)
}

Problem

My piece of code to remove short & long words from some text is: ``` # Remove Words based on lowerCutOff & upperCutOff removeByLength<- function(text,lowerCutOff=2,upperCutOff=12){ text<- gsub("\\b[a-zA-Z0-9]{1,lowerCutOff}\\b|\\b[a-zA-Z0-9]{upperCutOff,}\\b"," ",text) return(text) } ``` How can I achieve the needed functionality without hardcoding the lower & upper cutoffs?

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