Collapse continuous integer runs to strings of ranges

Question

I have some data in a list that I need to look for continuous runs of integers (My brain thinkrle but don\'t know how to use it here).

It\'s easier to l

Answer 1

I think diff is the solution. You might need some additional fiddling to deal with the singletons, but:

lapply(z, function(x) {
  diffs <- c(1, diff(x))
  start_indexes <- c(1, which(diffs > 1))
  end_indexes <- c(start_indexes - 1, length(x))
  coloned <- paste(x[start_indexes], x[end_indexes], sep=":")
  paste0(coloned, collapse=", ")
})

$greg
[1] "7:11, 20:24, 30:33, 49:49"

$researcher
[1] "42:48"

$sally
[1] "25:29, 37:41"

$sam
[1] "1:6, 16:19, 34:36"

$teacher
[1] "12:15"