Split a character vector into individual characters? (opposite of paste or stringr::str_c)

Yes, strsplit will do it. strsplit returns a list, so you can either use unlist to coerce the string to a single character vector, or use the list index [[1]] to access first element.

x <- paste(LETTERS, collapse = "")unlist(strsplit(x, split = ""))# [1] "A" "B" "C" "D" "E" "F" "G" "H" "I" "J" "K" "L" "M" "N" "O" "P" "Q" "R" "S"#[20] "T" "U" "V" "W" "X" "Y" "Z"

OR (noting that it is not actually necessary to name the split argument)

strsplit(x, "")[[1]]# [1] "A" "B" "C" "D" "E" "F" "G" "H" "I" "J" "K" "L" "M" "N" "O" "P" "Q" "R" "S"#[20] "T" "U" "V" "W" "X" "Y" "Z"

You can also split on NULL or character(0) for the same result.

str_extract_all() from stringr offers a nice way to perform this operation:

str_extract_all("ABCDEFGHIJKLMNOPQRSTUVWXYZ", boundary("character"))[[1]] [1] "A" "B" "C" "D" "E" "F" "G" "H" "I" "J" "K" "L" "M" "N" "O" "P" "Q" "R" "S" "T" "U"[22] "V" "W" "X" "Y" "Z"

This is rendered stepwise for clarity; in practice, a function would be created.

To find the number of times any character is repeated in sequence

the_string <- "BaaaaaaH"# split string into charactersthe_runs <- strsplit(the_string, "")[[1]]# find runsresult <- rle(the_runs)# find values that are repeatedresult$values[which(result$lengths > 1)]#> [1] "a"# retest with more runsthe_string <- "BaabbccH"# split string into charactersthe_runs <- strsplit(the_string, "")[[1]]# find runsresult <- rle(the_runs)# find values that are repeatedresult$values[which(result$lengths > 1)]#> [1] "a" "b" "c"