R/lsos.R

In martinbryan/WSC: Wallingford Senior Center

.ls.objects <- function(pos = 1, pattern, order.by,
                         decreasing = FALSE, head = FALSE, n = 5) {
  napply <- function(names, fn) sapply(names, function(x)
    fn(get(x, pos = pos)))
  names <- ls(pos = pos, pattern = pattern)
  obj.class <- napply(names, function(x) as.character(class(x))[1])
  obj.mode <- napply(names, mode)
  obj.type <- ifelse(is.na(obj.class), obj.mode, obj.class)
  obj.prettysize <- napply(names, function(x) {
    utils::capture.output(format(utils::object.size(x), units = "auto")) })
  obj.size <- napply(names, utils::object.size)
  obj.dim <- t(napply(names, function(x)
    as.numeric(dim(x))[1:2]))
  vec <- is.na(obj.dim)[, 1] & (obj.type != "function")
  obj.dim[vec, 1] <- napply(names, length)[vec]
  out <- data.frame(obj.type, obj.size, obj.prettysize, obj.dim)
  names(out) <- c("Type", "Size", "PrettySize", "Rows", "Columns")
  if (!missing(order.by))
    out <- out[order(out[[order.by]], decreasing = decreasing), ]
  if (head)
    out <- utils::head(out, n)
  out
}

#' Memory manage trick courtesy of Stack Exchange
#'
#' @param n How many objects to show.
#' @param ... Other optional arguments to .ls.objects
#'
#' @examples
#' \dontrun{
#' lsos(n = 10)
#' }
#'
#' @export
lsos <- function(..., n = 10) {
  .ls.objects(..., order.by = "Size", decreasing = TRUE, head = TRUE, n = n)
}