R: Want to check if any element of a set of words appear in a certain string

Question

Assuming I have a dataframe called items, and the first column is ItemNames. I'd like to go through each item in in items$ItemNames and check if they contain any of these words in:

words = c("apple","Apple","Pear","pear")

and if they do, replace the entire string with the word "confirmed".

What I've tried:

I used a combination of a for loop and if statement to do it but it failed:

search = function(x){
    words = c("apple","Apple","Pear","pear")
    for (i in length(x)){
        if (grepl(words, x[1][i]) == TRUE){  #where x[1][i] is the individual element in the ItemNames.
            x[1][i] = "confirmed"}
    }
}

search(items)

It didn't work. Ideally, I should have all the names in ItemNames replaced with "confirmed" if they contain any of the elements in words.

Were you trying to do exact matches or just partial matches? When asking for help you should include a [reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) with sample input and desired output. I think the duplicate answers your question but if not, edit your question to make your specific problem more clear and it can be re-opened. — MrFlick, Sep 08 '17 at 16:09

score 1 · Answer 1 · answered Sep 08 '17 at 16:18

Using stringr:

library(stringr)

words <- c("apple", "Apple", "Pear", "pear")
pattern <- paste(words, collapse = "|")

dt <- data.frame(
  ItemNames = c("Superb apple", "Superb Pear", "Superb car"), 
  Cost = c(1, 2, 3),
  stringsAsFactors = FALSE
)

index <- str_detect(dt$ItemNames, regex(pattern))
dt[index,]$ItemNames <- "confirmed"

R: Want to check if any element of a set of words appear in a certain string

1 Answers1