R/TOCsp.R

In TOC: Total Operating Characteristic Curve and ROC Curve

.TOCsp <- function(index, boolean, mask = NULL, nthres = NULL, thres = NULL, NAval = 0, P = NA, Q = NA, progress = FALSE) {
  
  if(!is.null(nthres) & !is.null(thres)) stop("Enter nthres OR thres as input to define thresholds, not both at the same time")
  
  # extract cell values from the boolean and index maps 
  boolval <- values(boolean, mat = FALSE)
  indval <- values(index, mat = FALSE)
  
  # extract cell values from the mask map if given
  if(!is.null(mask)) mask <- values(mask, mat = FALSE)
  
  # calculate population 
  # mask out nodata cells in the index and boolean vectors if a mask vector is given
  if(!is.null(mask)){
    mask[mask == NAval] <- NA
    boolval <- boolval * mask
  }
  # extract total number of cells with ones and zeros in the boolean vector
  boolvals <- boolval[!is.na(boolval)]
  ones.bool <- sum(as.bit(boolvals))
  zeros.bool <- length(boolvals) - ones.bool
  
  validPixels <- ones.bool + zeros.bool
  
  population <- validPixels * res(index)[1] * res(index)[2]
  if(!is.na(P) & !is.na(Q)){
    population <- P + Q
  }
  
  # extract map units for plotting purposes with plot.TOC
  units <- paste("square", strsplit(strsplit(crs(index, proj = TRUE), "+units=")[[1]][2], " ")[[1]][1])
  
  tocd <- .TOCnosp(indval, boolval, mask = mask, nthres = nthres, thres = thres, NAval = NAval, progress = progress, 
                   ones.bool = ones.bool, zeros.bool = zeros.bool, population = population, units = units)
  
  return(tocd) 
}