ncdf4_ext.R

#' Get the detail of ncdf4 file variable as a data.frame
#'
#' @param nc opened nc4 files
#' @return data.frame of variable information
#' @keywords nc attibute
#' @export
#' @examples
#' ncatt_get_df(nc)
ncatt_get_df <- function(nc, items=c("long_name", "units")){
  options(stringsAsFactors=FALSE)
  var.names <- as.vector(names(nc$var))
  var.list <- lapply(var.names, function(var) ncatt_get(nc, var))
  var.list.items <- lapply(1:length(var.list), function(i) var.list[[i]][items])
  var.df <- do.call("rbind", lapply(var.list.items, data.frame))
  # var.df <- plyr::ldply(var.list, data.frame)  # altertive is using ldply
  var.df <- cbind(var=var.names, var.df)
  return(var.df)
}