R/tll.R

In kimisc: Kirill's Miscellaneous Functions

#' @title Transposes a list of lists
#' @description The argument is assumed to be a list of \eqn{n} (named) lists
#'   with length \eqn{m} each.  It is converted to a (named) list of \eqn{m}
#'   elements with length \eqn{n} each.
#' @param l List of lists, possibly named.
#' @return A list of lists corresponding to a transposition of the argument.
#' @seealso [base::t()]
#' @examples
#' tll(list(list(1, 2), list(3, 4)))
#' tll(list(list(a = 1, b = 2), list(a = 3, b = 4)))
#' tll(list(x = list(a = 1, b = 2), y = list(a = 3, b = 4)))
#' @export
#' @family deprecated functions
#' @name tll-deprecated
#' @keywords internal
tll <- function(l) {
  deprecate("purrr::transpose")
  if (length(l) == 0) {
    return(list())
  }

  plyr::llply(
    setMissingNames(object = seq_along(l[[1]]), nm = names(l[[1]])),
    function(n) {
      plyr::llply(l, function(ll) ll[[n]])
    }
  )
}