R/showMemoryUse.R

In John-Poplett/novels: Predicting Success of Literary Texts

#' A pretty=printer that shows memory use in current session
#' @param sort specify sort by "size" or "alphabetical". Default = "size".
#' @param decreasing show results in decreasing size order. Default = False.
#' @param limit limit listing to specified value. Default = all.
#' @importFrom utils object.size
#' @export
showMemoryUse <- function(sort="size", decreasing=FALSE, limit) {

  objectList <- ls(parent.frame())

  oneKB <- 1024
  oneMB <- 1048576
  oneGB <- 1073741824

  memoryUse <- sapply(objectList, function(x) as.numeric(object.size(eval(parse(text=x)))))

  memListing <- sapply(memoryUse, function(size) {
    if (size >= oneGB) return(paste(round(size/oneGB,2), "GB"))
    else if (size >= oneMB) return(paste(round(size/oneMB,2), "MB"))
    else if (size >= oneKB) return(paste(round(size/oneKB,2), "kB"))
    else return(paste(size, "bytes"))
  })

  memListing <- data.frame(objectName=names(memListing),memorySize=memListing,row.names=NULL)

  if (sort=="alphabetical") memListing <- memListing[order(memListing$objectName,decreasing=decreasing),]
  else memListing <- memListing[order(memoryUse,decreasing=decreasing),] #will run if sort not specified or "size"

  if(!missing(limit)) memListing <- memListing[1:limit,]

  print(memListing, row.names=FALSE)
  return(invisible(memListing))
}