How to generate random words from a list of characters?

Question

I would like to generate a list of 50 words from the letters "a b c d". every word should have 5 characters. every word has to be different from the others in at least 2 positions (letters) using base R.

x="a,b,c,d"

and results should be list of 50 words:

l=['abcda','cdabd','bdaca'.......]

expand.grid function in R generate words with only 1 letter difference.

Answer 1

If you want to sample from a complete set of words, you can first construct such complete set as the first step (see X in the code below), and then you can reuse it for multiple times by running sample(X, 50) simply

v <- do.call(paste0, expand.grid(rep(list(letters[1:4]), 5)))
X <- Reduce(
  function(S, k) {
    if (all(adist(k, S) >= 2)) {
      S <- c(S, k)
    }
    S
  }, v
)
res <- sample(X, 50)

---

Another option is using while loop and keeping the set of selected words updated in each iteration

res <- paste0(sample(letters[1:4], 5, replace = TRUE), collapse = "")
while (length(res) < 50) {
  k <- paste0(sample(letters[1:4], 5, replace = TRUE), collapse = "")
  if (all(adist(k, res) >= 2)) {
    res <- c(res, k)
  }
}
res