Merge remote-tracking branch 'origin/developJEZ' into develop

R/groupByDistrict.R

@@ -0,0 +1,48 @@
+#Copyright © 2016 RTE Réseau de transport d’électricité
+
+#' aggregate a data.table by district
+#'
+#' @param x
+#'   data.table containing at least a column area.
+#' @param opts
+#'   simulation options returned with simOptions()
+#' @param fun
+#'   vector of functions with size equal to the number of columns to aggregate
+#'   (number of columns - number of id columns). If it is of length 1, the
+#'   function is used for all columns.
+#'
+#' @return
+#' A data.table with the same columns as the input except that the column area
+#' is replaced by column district.
+#'
+#' @note
+#' This is a private function that is used in functions like surplus that require
+#' detailed data by area, but user may want aggregated output.
+#'
+#' @noRd
+#'
+.groupByDistrict <- function(x, opts, fun = c(sum)) {
+  x <- merge(x, opts$districtsDef, by = "area", allow.cartesian = TRUE)
+
+  # Check that all nodes from a district are in the data
+  areasInData <- unique(x$area)
+  districts <- intersect(x$district, opts$districtsDef$district)
+  districtsDef <- split(opts$districtsDef$area, opts$districtsDef$district)
+
+  for (d in districts) {
+    missingAreas <- setdiff(districtsDef[[d]], areasInData)
+
+    if (length(missingAreas) > 0) warning("The following areas belongs to district ", d, " but are not in 'x': ",
+                                          paste(missingAreas, collapse = ", "))
+  }
+
+  # Aggregation by district
+  x[, area := NULL]
+  idVars <- .idCols(x)
+
+  if (length(fun) == 1) fun <- rep(fun, ncol(x) - length(idVars))
+
+  x[, mapply(function(x, f) {f(x)}, x = .SD, f = fun, SIMPLIFY=FALSE),
+    by = idVars]
+
+}