R/SurvDat.R

In jpasquier/ad_test: What the Package Does (One Line, Title Case)

#' Generate the survival data
#'
#' Generate a dataframe containing observed durations (surv) and censoring
#' indicators (cens) for each individual
#'
#' @param id ids in the longitudinal dataset
#' @param time observation times in the longitudinal dataset
#' @param cens censoring indicator in the longitudinal dataset (has to be
#'     uniquely defined by id)
#'
#' @return a dataframe containing observed durations (surv) and censoring
#' indicators (cens) for each individual
#'
#' @examples
#' data(onco)
#' SurvDat(onco$id, onco$drel, onco$cens)
#'
#' @export

SurvDat <- function(id, time, cens) {
  # look for last observation time for each id
  last <- aggregate(time, list(id), max)
  names(last) <- c("id", "surv")
  # add one unit to get survival time
  last$surv <- last$surv + 1
  # check that censoring indicator is uniquely defined for each id
  if(any(aggregate(cens, list(id), function(z) length(unique(z)) > 1)[[2]])) {
    stop("censoring indicator is not uniquely defined for each id")
  }
  # get censoring indicator for each id
  ind <- aggregate(cens, list(id), unique)
  names(ind) <- c("id", "cens")
  # merge survival time and censoring indicator
  surv <- merge(last, ind, by = "id")
  return(surv)
}