Ranger case weights (#2418)

* add case weights and repair minprop

* solve case.weights problem

Author: PhilippPro

R/RLearner_classif_ranger.R

@@ -36,7 +36,7 @@ makeRLearner.classif.ranger = function() {
 }
 
 #' @export
-trainLearner.classif.ranger = function(.learner, .task, .subset, .weights = NULL, mtry, mtry.perc, min.node.size, ...) {
+trainLearner.classif.ranger = function(.learner, .task, .subset, .weights = NULL, mtry, mtry.perc, min.node.size, case.weights, ...) {
   tn = getTaskTargetNames(.task)
   if (missing(mtry)) {
     if (missing(mtry.perc)) {
@@ -52,8 +52,11 @@ trainLearner.classif.ranger = function(.learner, .task, .subset, .weights = NULL
       min.node.size = 1
     }
   }
+  if (missing(case.weights)) {
+    case.weights = .weights
+  }
   ranger::ranger(formula = NULL, dependent.variable = tn, data = getTaskData(.task, .subset),
-                 probability = (.learner$predict.type == "prob"), case.weights = .weights, mtry = mtry, min.node.size = min.node.size, ...)
+                 probability = (.learner$predict.type == "prob"), case.weights = case.weights, mtry = mtry, min.node.size = min.node.size, ...)
 }
 
 #' @export

R/RLearner_regr_ranger.R

@@ -38,7 +38,7 @@ makeRLearner.regr.ranger = function() {
 }
 
 #' @export
-trainLearner.regr.ranger = function(.learner, .task, .subset, .weights = NULL, keep.inbag = NULL, mtry, mtry.perc, ...) {
+trainLearner.regr.ranger = function(.learner, .task, .subset, .weights = NULL, keep.inbag = NULL, mtry, mtry.perc, case.weights, ...) {
   tn = getTaskTargetNames(.task)
   if (missing(mtry)) {
     if (missing(mtry.perc)) {
@@ -47,10 +47,13 @@ trainLearner.regr.ranger = function(.learner, .task, .subset, .weights = NULL, k
       mtry = max(1, floor(mtry.perc * getTaskNFeats(.task)))
     }
   }
+  if (missing(case.weights)) {
+    case.weights = .weights
+  }
   keep.inbag = if (is.null(keep.inbag)) FALSE else keep.inbag
   keep.inbag = if (.learner$predict.type == "se") TRUE else keep.inbag
   ranger::ranger(formula = NULL, dependent.variable = tn, data = getTaskData(.task, .subset),
-                 case.weights = .weights, keep.inbag = keep.inbag, mtry = mtry, ...)
+                 case.weights = case.weights, keep.inbag = keep.inbag, mtry = mtry, ...)
 }
 
 #' @export