R/pfMinMax.R

In oblarquez/paleofire: Analysis of Charcoal Records from the Global Charcoal Database

#' MiniMax transformation of a charcoal serie
#'
#' MiniMax transformation of a charcoal serie
#'
#'
#' @param serie Numeric, a vector of charcoal values.
#' @return \item{out}{A vector of minimax transformed values.}
#' @author O. Blarquez
#' @seealso \code{\link{pfTransform}}
#' @examples
#'
#' ## Retrieve a site
#' ID=pfSiteSel(site_name=="Pas-de-Fond")
#' ## Or a group of sites
#' ID=pfSiteSel(continent=="Africa")
#'
#' ## Extract data
#' A=pfExtract(ID)
#'
#' ## Plot the first site raw charcoal data
#' par(mfrow=c(1,2))
#' plot(A[A[,1]==ID$id_site[1],3],A[A[,1]==ID$id_site[1],4],type="l",main=ID$site_name[1],
#'      xlab="Age",ylab="raw Char")
#' ## Minimax transformation
#' B=pfMinMax(A[A[,1]==ID$id_site[1],4])
#' ## Plot the first site Minimax transformed charcoal data
#' plot(A[A[,1]==ID$id_site[1],3],B,type="l",main=ID$site_name[1],
#'      xlab="Age",ylab="Minimax")
#'
pfMinMax <- function(serie) {
  # Minimax transformation
  serie <- (serie - min(serie, na.rm = TRUE)) / (max(serie, na.rm = TRUE) - min(serie, na.rm = TRUE))
  return(serie)
}