lulcc2: Land Use Change Modelling in R

#' Class LulcRasterStack
#'
#' A virtual S4 class for observed land use maps.
#'
#' @slot filename see \code{raster::\link[raster]{Raster-class}}
#' @slot layers see \code{raster::\link[raster]{Raster-class}}
#' @slot title see \code{raster::\link[raster]{Raster-class}}
#' @slot extent see \code{raster::\link[raster]{Raster-class}}
#' @slot rotated see \code{raster::\link[raster]{Raster-class}}
#' @slot rotation see \code{raster::\link[raster]{Raster-class}}
#' @slot ncols see \code{raster::\link[raster]{Raster-class}}
#' @slot nrows see \code{raster::\link[raster]{Raster-class}}
#' @slot crs see \code{raster::\link[raster]{Raster-class}}
#' @slot history see \code{raster::\link[raster]{Raster-class}}
#' @slot z see \code{raster::\link[raster]{Raster-class}}
#' @slot t numeric vector with timesteps corresponding to each observed map
#' @slot categories numeric vector of land use categories
#' @slot labels character vector corresponding to \code{categories}
#' 
#' @export
#' @exportClass LulcRasterStack
#' @rdname LulcRasterStack-class
setClass("LulcRasterStack",
         contains = c("RasterStack"),
         slots = c(
             t = "numeric", 
             categories = "numeric",
             labels = "character"),
         validity = function(object) {
             return(TRUE)
         }
         )

#' Class DiscreteLulcRasterStack
#'
#' A virtual S4 class for observed land use maps.
#'
#' @slot filename see \code{raster::\link[raster]{Raster-class}}
#' @slot layers see \code{raster::\link[raster]{Raster-class}}
#' @slot title see \code{raster::\link[raster]{Raster-class}}
#' @slot extent see \code{raster::\link[raster]{Raster-class}}
#' @slot rotated see \code{raster::\link[raster]{Raster-class}}
#' @slot rotation see \code{raster::\link[raster]{Raster-class}}
#' @slot ncols see \code{raster::\link[raster]{Raster-class}}
#' @slot nrows see \code{raster::\link[raster]{Raster-class}}
#' @slot crs see \code{raster::\link[raster]{Raster-class}}
#' @slot history see \code{raster::\link[raster]{Raster-class}}
#' @slot z see \code{raster::\link[raster]{Raster-class}}
#' @slot t numeric vector with timesteps corresponding to each observed map
#' @slot categories numeric vector of land use categories
#' @slot labels character vector corresponding to \code{categories}
#' 
#' @export
#' @exportClass DiscreteLulcRasterStack
#' @rdname DiscreteLulcRasterStack-class
setClass("DiscreteLulcRasterStack",
         contains = c("LulcRasterStack"),
         ## slots = c(
         ##   t = "numeric",
         ##   categories = "numeric",
         ##   labels = "character"),
         validity = function(object) {
             check1 <- (raster::nlayers(object) > 0)
             if (!check1) stop("RasterStack contains no layers")
             check2 <- (length(object@t) == raster::nlayers(object))
             if (!check2) stop("timesteps do not correspond with maps")
             if (raster::canProcessInMemory(object)) {
                 check3 <- all(sort(unique(as.numeric(raster::getValues(object)))) %in% object@categories)
             } else {
                 warning("Cannot process in memory")
                 check3 <- TRUE
             }
             if (!check3) stop("unknown categories in maps")
             check4 <- (length(object@categories) == length(object@labels))
             if (!check4) stop("labels and categories have different lengths")
             return(TRUE)
         }
)

#' Class ContinuousLulcRasterStack
#'
#' A virtual S4 class for observed land use maps.
#'
#' @slot filename see \code{raster::\link[raster]{Raster-class}}
#' @slot layers see \code{raster::\link[raster]{Raster-class}}
#' @slot title see \code{raster::\link[raster]{Raster-class}}
#' @slot extent see \code{raster::\link[raster]{Raster-class}}
#' @slot rotated see \code{raster::\link[raster]{Raster-class}}
#' @slot rotation see \code{raster::\link[raster]{Raster-class}}
#' @slot ncols see \code{raster::\link[raster]{Raster-class}}
#' @slot nrows see \code{raster::\link[raster]{Raster-class}}
#' @slot crs see \code{raster::\link[raster]{Raster-class}}
#' @slot history see \code{raster::\link[raster]{Raster-class}}
#' @slot z see \code{raster::\link[raster]{Raster-class}}
#' @slot t numeric vector with timesteps corresponding to each observed map
#' @slot categories numeric vector of land use categories
#' @slot labels character vector corresponding to \code{categories}
#' 
#' @export
#' @exportClass ContinuousLulcRasterStack
#' @rdname ContinuousLulcRasterStack-class
setClass("ContinuousLulcRasterStack",
         contains = c("LulcRasterStack"),
         ## slots = c(
         ##   t = "numeric",
         ##   categories = "numeric",
         ##   labels = "character"),
         validity = function(object) {
             ## TODO: check all values 0 <= val <= 1
             check1 <- (raster::nlayers(object) > 0)
             if (!check1) stop("RasterStack contains no layers")
             ## check2 <- raster::nlayers(object) == (length(object@t) * length(object@categories))
             ## if (!check2) stop("TODO")
             check3 <- (length(object@categories) == length(object@labels))
             if (!check3) stop("labels and categories have different lengths")
             return(TRUE)
         }
)