Merge pull request #590 from ESCRI11/v6.3.3.-dev-panelaggregration

fix: port panelaggragation fct

Author: StuartWheater

NAMESPACE

@@ -1,5 +1,6 @@
 # Generated by roxygen2: do not edit by hand
 
+export(computeWeightedMeans)
 export(ds.Boole)
 export(ds.abs)
 export(ds.asCharacter)
@@ -119,3 +120,7 @@ export(ds.var)
 export(ds.vectorCalc)
 import(DSI)
 import(data.table)
+importFrom(stats,as.formula)
+importFrom(stats,na.omit)
+importFrom(stats,ts)
+importFrom(stats,weighted.mean)

R/computeWeightedMeans.R

@@ -0,0 +1,25 @@
+#' Compute Weighted Mean by Group
+#' 
+#' This function is originally from the panelaggregation package.
+#' It has been ported here in order to bypass the package being
+#' kicked off CRAN.
+#' 
+#' @author Matthias Bannert, Gabriel Bucur
+#' @param data_table a data.table
+#' @param variables character name of the variable(s) to focus on. The variables must be in the data.table
+#' @param weight character name of the data.table column that contains a weight. 
+#' @param by character vector of the columns to group by
+#' @import data.table
+#' @importFrom stats as.formula na.omit ts weighted.mean
+#' @export
+computeWeightedMeans <- function(data_table, variables, weight, by) {
+  
+  if (is.null(weight)) {
+    res_dt <- data_table[, lapply(.SD, mean, na.rm = TRUE), .SDcols = variables, by = by]
+  } else {
+    res_dt <- data_table[, lapply(.SD, weighted.mean, weight = eval(as.name(weight)), na.rm = TRUE),
+                         .SDcols = variables, by = by]
+  }
+  
+  res_dt
+}