R/find.R

In r4ecology/rcdo: Tools to manipulate netcdf data

#' @title search netcdf files in folder
#'
#' @description This function will list the netcdf files in a directory that contain a specified variable
#' @param directory This is the directory to check.
#' @param vars a character string of the variable to search for
#' @return list of files
#' @export

nc_find <- function(directory = getwd(), var = NULL, recursive = TRUE) {
  setwd(directory)
  on.exit(setwd(getwd()))

  if (is.null(var)) {
    stop("error: no variable named")
  }
  if (length(var) > 1) {
    stop("error: more than one variable given")
  }

  print("getting here")

  # step 1. Get a list of netcdf files in the folder
  all_files <- dir(directory, recursive = recursive) %>%
    tibble::enframe(name = NULL) %>%
    dplyr::rename(File = value) %>%
    dplyr::filter(endsWith(File, ".nc"))
  print("getting here slowly?")

  #
  contains_var <- function(ff) {
    print(stringr::str_glue("searching {ff}"))
    var %in% nc_variables(ff)
  }

  all_files <- all_files %>%
    dplyr::mutate(contains = purrr::map_lgl(File, contains_var)) %>%
    dplyr::filter(contains) %>%
    dplyr::select(File) %>%
    dplyr::pull(File)

  all_files
}