R/tagnfuse.R

In ALanguillaume/tagnfuse: Implement tag and fuse workflow

#' @title Tag a list of data.frames.
#'
#' @description  Takes a list of data.frames and "tag" each my adding a column
#' containing the name of the list container they belong to. The tags can later
#' be used as a factor when "fusing" the list in a single data.frame.
#'
#' @param list_df A list of data.frames.
#' @param label A single character string containing the name of the tagged column.
#'
#' @return A tagged list of data.frames.
#'
#' @importFrom purrr map_dbl map2 pmap
#' @export

tag <- function(list_df, label = "tag"){

  it <- purrr::map_dbl(list_df, nrow)
  l_tag <- purrr::map2(names(list_df), it, ~ rep(.x, each = .y))

  l_args <- list(list_df, label, l_tag)

  tag_atom <- function(x, y, z){
    x[[y]] <- z
    return(x)
  }

  list_df <- purrr::pmap(l_args, tag_atom)

  return(list_df)
}


#' @title Fuse list of data.frames
#'
#' @description Applies purrr::reduce(rbind) to a list of data.frames with the
#' same columns.
#'
#' @param list_df A list of data.frames with the same columns.
#'
#' @return A fused data.frame
#'
#' @importFrom purrr reduce
#' @export

fuse <- function(list_df){
  purrr::reduce(list_df, rbind)
}


#' Tag and fuse workflow
#'
#' @param list_df A list of data.frames with the same columns.
#'
#'
#' @export

tagnfuse <- function(list_df, label = "tag"){
  fuse(tag(list_df, label = label))
  }