R/morph.R

In beerda/hexmatrix: What the Package Does (One Line, Title Case)

#' @export
morph <- function(m, dilate=TRUE, na.rm=FALSE) {
  assert_that(is.flag(dilate))
  assert_that(is.flag(na.rm))

  if (is.hexmatrix(m)) {
    f <- ifelse(dilate, pmax, pmin)
    n <- neighbours(m, self=TRUE)
    res <- f(n[, , 1],
             n[, , 2],
             n[, , 3],
             n[, , 4],
             n[, , 5],
             n[, , 6],
             n[, , 7],
             na.rm=TRUE)
    res <- array(as.logical(res), dim=dim(m))
    if (!na.rm) {
      naMask <- morph(is.na(m), dilate=TRUE, na.rm=TRUE)
      res[naMask] <- NA
    }
    return(res)

  } else if (is.hexarray(m)) {
    res <- like(m, data=FALSE)
    for (l in seq_len(nlayer(m))) {
      res[, , l] <- morph(m[, , l], dilate=dilate, na.rm=na.rm)
    }
    return(res)
  }
}