R/median.factor.R

In RVAideMemoire: Testing and Plotting Procedures for Biostatistics

median.factor <-
  if("..." %in% names(formals(median))) {
    function (x,na.rm=TRUE,...) {
	if (!is.ordered(x)) {stop(paste0(deparse(substitute(x))," is not ordered"))}
	med.num <- median(as.numeric(x),na.rm=na.rm,...)
	if ((med.num/0.5)%%2==1) {med.num <- c(floor(med.num),ceiling(med.num))}
	med.lev <- paste(levels(x)[med.num],collapse=",")
	med.lev
    }
  } else {
    function (x,na.rm=TRUE) {
	if (!is.ordered(x)) {stop(paste0(deparse(substitute(x))," is not ordered"))}
	med.num <- median(as.numeric(x),na.rm=na.rm)
	if ((med.num/0.5)%%2==1) {med.num <- c(floor(med.num),ceiling(med.num))}
	med.lev <- paste(levels(x)[med.num],collapse=",")
	med.lev
    }
  }