String split with conditions in R

Question

I have this mystring with the delimiter _. The condition here is if there are two or more delimiters, I want to split at the second delimiter and if th

Answer 1

A little longer, but needs less regular expression knowledge:

library(stringr)
indx <- str_locate_all(mystring, "_")

for (i in seq_along(indx)) {
  if (nrow(indx[[i]]) == 1) {
    mystring[i] <- strsplit(mystring[i], ".ReCal")[[1]][1]
  } else {
    mystring[i] <- substr(mystring[i], start = 1, stop = indx[[i]][2] - 1)
  }
}