R/malmquist.R

In pik-piam/magpie4: MAgPIE outputs R package for MAgPIE version 4.x

#' @title malmquist
#' @description calcluates malmquist index based on a MAgPIE gdx file
#' @export
#' @param gdx GDX file
#' @param file a file name the output should be written to using write.magpie
#' @return A MAgPIE object containing the malmquist index
#' @author Xiaoxi Wang
#' @importFrom nonparaeff faremalm2
#' @importFrom reshape2 melt
#' @importFrom stats reshape
#' @examples
#'   \dontrun{
#'     x <- malmquist(gdx)
#'   }
malmquist <- function(gdx, file = NULL) {
  #please add to arguments (we need "reg", "glo" and "regglo"; superAggreate can handle this; see other functions)
  level <- "reg"
  production <- setNames(production(gdx, level = level, product_aggr = TRUE), "production")
  costs <- setNames(costs(gdx, level = level, type = "annuity", sum = FALSE)[, , "Input Factors"], "factorcosts")
  cropland <- setNames(land(gdx, level = level, types = "crop"), "cropland")
  water <- setNames(water_usage(gdx, level = level)[, , "agriculture", drop = TRUE], "water")
  x <- mbind(production, costs, cropland, water)
  d <- as.data.frame(x, rev = 2)
  if (level == "reg") {
    d <- reshape(d, timevar = "data1", idvar = c("t", "i"), direction = "wide")
  } else {
    d <- reshape(d, timevar = "data1", idvar = c("t", "i", "j"), direction = "wide")
    d$i <- paste(d$i, d$j, sep = "_")
    d$j <- NULL
  }
  d$i <- as.factor(d$i)
  d$t <- as.factor(d$t)
  years <- levels(d$t)
  d$t <- as.numeric(d$t)
  names(d) <- gsub(".value.", "", names(d), fixed = TRUE)
  m <- faremalm2(dat = d, noutput = 1, id = "i", year = "t")
  m$t <- as.factor(m$t)
  levels(m$t) <- paste(years[-length(years)], years[-1], sep = "-")
  m <- suppressMessages(melt(m))
  m <- (as.magpie(m, tidy = TRUE, temporal = 2))
  out(m, file)
}