R/mHM_reclassint.R

In JBrenn/mHMr: pre- and post-prossesing for mHM

#' Reclassify raster with lookuptable. 
#' 
#' \code{mHM_reclassint} reclassifies a raster map, e.g. CORINE land use, to specific classes for usage in mHM.
#' 
#' 
#' 
#' @param rst raster object.
#' @param lookuptbl lookup table, e.g. given by \code{data(luse_reclass)}.
#' @param tif boolean, if TRUE output raster written in GEOtif format.
#' @param asc boolean, if TRUE output raster written in ASCII format.
#' @param varname character, variable name.
#' 
#' @return reclassified raster object.
#' 
#' @examples
#' library(raster)
#' 
#' data(corine_jucar)
#' corine_jucar <- as.raster(corine_jucar)
#' plot(corine_jucar)
#' 
#' data(luse_reclass)
#' luse_reclass <- as.matrix(luse_reclass)
#' 
#' mHMluse_jucar <- mHM_reclassint(rst=corine_jucar, lookuptbl=luse_reclass_tbl, tif=F, asc=F, varname="luse")
#' plot(mHMluse_jucar)
#' 
#' @author Johannes Brenner \email{johannes.brenner@ufz.de}
#' 
#' @references
#' 
#' @seealso
#' 
#' @keywords
#' 
#' @export mHM_reclassint
#' 

mHM_reclassint <- function(rst, lookuptbl, tif=F, asc=F, varname="luse")
{
  # raster map --> .acs

  # reclassify values according to lookuptbl
  print("reclassifying")
  rst_reclass <- raster::reclassify(x = rst, rcl = lookuptbl)
  
  # write back .asc and .tif
  if (asc)
  {
    print("writing raster")
    raster::writeRaster(x = rst_reclass, filename = paste(varname,".asc",sep=""), overwrite=TRUE)
  }
  if (tif)
  {
    print("writing geotif")
    raster::writeRaster(x = rst_reclass, filename = paste(varname,".tif",sep=""), overwrite=TRUE)
  }
    
  return(rst_reclass)
}

  # convert corine land cover data to mHM lai input
  # raster map --> .acs
  # reclassify to 3 lai classes: 
  # (1) coniferious forest
  # (2) deciduous forest
  # (3) mixed forest
  # (4) sparesly populated forest
  # (5) sealed water bodys
  # (6) viniculture
  # (7) intensive orchards
  # (8) pastures
  # (9) fields
  #(10) wetlands
  #(11) artificial surfaces
  #(12) arable land (non-irrigated)
  #(13) arable land (irrigated)

  # convert corine land cover data to mHM luse input  
  # reclassify to 3 land use types: 
  # (1) forest
  # (2) impervious
  # (3) pervious