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

[Bart Joosen]

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)
min(which(x==1))))
  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

Bart
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