R/write.gra.R

In R2BayesX: Estimate Structured Additive Regression Models with 'BayesX'

write.gra <- function(map, file, replace=FALSE)
{
  if(!inherits(map, "gra"))
    stop("Argument 'map' is not an object of class 'gra'!")

  ## check whether the file exists
  if(replace & file.exists(file))
    test <- file.remove(file)
  if(!replace & file.exists(file))
    stop("Specified file already exists!")

  ## names of districts
  districts <- as.integer(rownames(map))

  ## no. of regions
  S <- length(districts)
  write(S, file)

  ## loop over the regions
  for(i in 1:S){
    ## write name of the district
    write(districts[i], file, append=TRUE)
        
    ## write no. of neighbors
    write(map[i,i], file, append=TRUE)

    ## derive and write neighbors
    ind <- which(map[i, ] == -1) - 1

    write(ind, file, ncolumns = length(ind), append = TRUE)
  }

  return(invisible(NULL))
}