R/add_area_names.R

In SWS-Methodology/faoswsTrade: FAO Trade Module

#' A function to add columns with area names to a data frame where reporter or
#' partner columns exist.
#'
#' @param data A data frame where reporter or partner columns exists.
#' @param code_class A character string indicating classification of area codes:
#'   "fao", "m49" or "geonom".
#' @param area_columns A character vector indicating names of columns with area
#'   codes. By default c("reporter", "partner").
#' @return Original data frame with added columns with name "name" (one column)
#'   or suffix "_name" (several columns).
#' @export
#' @import dplyr

add_area_names <- function(data, code_class = NULL,
                           area_columns = c("reporter", "partner")) {

  stopifnot(!is.null(code_class))
  code_class <- tolower(code_class)

  if (!code_class %in% c("fao", "m49", "geonom"))
    stop("Unknown area code class. Please use `fao`, `m49` or `geonom`.")

  columns2change <- colnames(data)[colnames(data) %in% area_columns]

  if (length(columns2change) == 0L) {
    message("No suitable columns detected. Nothing to do.")
    return(data)
  }

  data <- data %>%
    mutate_at(columns2change, funs(name = name_area(., code_class = code_class)))

  data

}