[R] Selecting the first occurrence of a value after an occurrence of a different value

Bart Joosen bartjoosen at hotmail.com
Fri Jan 14 12:21:02 CET 2011

Ofcourse you can loop over your data, but a vectorised way:

f.search <- function(x, ref, search) {
  cs <- match(cumsum(x==ref), cumsum(x==ref))
  outp <- suppressWarnings(tapply(x==search,cs, function(x)
  outp <- outp[outp!=Inf] # To remove the occurences where nothing was found
  return(as.vector(as.numeric(names(outp))+outp - 1))

f.search(x, "MagDwn", "Resp")

Good luck

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