add c4r vocabulary

DESCRIPTION

@@ -1,9 +1,10 @@
 Package: climate4R.UDG
 Depends:
-    R(>= 3.5.0)
+    R(>= 3.5.0),
+    rJava
 Imports:
     utils,
-    RCurl
+    RCurl,
 Suggests:
     loadeR,
     loadeR.ECOMS,

NAMESPACE

@@ -1,9 +1,13 @@
 # Generated by roxygen2: do not edit by hand
 
+export(C4R.vocabulary)
+export(C4R.vocabulary.update)
 export(UDG.datasets)
 export(loginUDG)
 importFrom(RCurl,getURL)
+importFrom(rJava,J)
 importFrom(utils,URLencode)
 importFrom(utils,globalVariables)
 importFrom(utils,packageDescription)
 importFrom(utils,read.csv)
+importFrom(utils,write.table)

R/loginUDG.R

@@ -12,6 +12,7 @@
 #'  Further details on registration for data access can be viewed in this \href{http://meteo.unican.es/trac/wiki/udg/registration}{example}.
 #' @author J Bedia, M. Vega, A. Cofino
 #' @export
+#' @importFrom rJava J
 #' @importFrom RCurl getURL
 #' @importFrom utils URLencode
 

R/vocabulary.R

@@ -0,0 +1,54 @@
+#' @title Show UDG vocabulary
+#' @description Access the installed user's vocabulary
+#' @return The vocabulary table, in the form of a data.frame
+#' @seealso C4R.vocabulary.update, for the inclusion of new standard variables defined by the user
+#' @note The function assumes that the user has read permission to the package installation directory
+#' @author J Bedia
+#' @references Standard name table of the CF convention: http://cfconventions.org/standard-names.html
+#' @export
+#' @importFrom utils read.csv
+#' @examples
+#' # Default built-in vocabulary
+#' (voc <- C4R.vocabulary())
+#' voc[grep("^ta", voc$identifier), ]
+
+C4R.vocabulary <- function() {
+      read.csv(file.path(find.package("loadeR"), "vocabulary.txt"))
+}
+
+#' @title Include new variables in the vocabulary
+#' @description Allows the introduction of new user defined entries in the default vocabulary
+#' @return The built-in vocabulary is updated with the new entries appended at the end.
+#' @param identifier A vector containing the identifier(s) of the new variable(s) to be appended to the dictionary. 
+#' @param standard_name A vector containing the standard name(s) of the new variable(s) to be appended to the dictionary. 
+#' @param units A vector containing the units of the new variable(s) to be appended to the dictionary. 
+#' @seealso C4R.vocabulary, to access the vocabulary contents
+#' @export
+#' @importFrom utils write.table
+#' @author J Bedia
+#' @references Standard name table of the CF convention: http://cfconventions.org/standard-names.html
+#' @examples \dontrun{
+#' # Inclusion of a new variable ("Total snowfall amount")
+#' C4R.vocabulary.update(identifier = "prsn",
+#'                  standard_name = "total snowfall amount",
+#'                  units = "mm")
+#' C4R.vocabulary()                 
+#' # Inclusion of 2 new variables: 
+#' C4R.vocabulary.update(identifier = c("wap",
+#'                                 "plev"),
+#'                  standard_name = c("lagrangian tendency of air pressure",
+#'                                    "air pressure"),
+#'                  units = c("Pa.s-1",
+#'                            "Pa"))
+#' C4R.vocabulary() 
+#' }
+
+C4R.vocabulary.update <- function(identifier, standard_name, units) {
+      ref <- C4R.vocabulary()
+      if (any(identifier %in% ref$identifier)) {
+            stop("One or more identifiers already exist in the vocabulary", call. = FALSE)      
+      }
+      a <- cbind(identifier, standard_name, units)
+      write.table(a, append = TRUE, file = file.path(find.package("loadeR"), "vocabulary.txt"),
+                  quote = FALSE, row.names = FALSE, sep = ",", col.names = FALSE)
+}