Merge pull request #106 from StochasticTree/single-tree-predict

Added R method for single tree prediction

Author: andrewherren

R/forest.R

@@ -101,7 +101,7 @@ ForestSamples <- R6::R6Class(
         #' @param forest_dataset `ForestDataset` R class
         #' @param forest_num Index of the forest sample within the container
         #' @return matrix of predictions with as many rows as in forest_dataset 
-        #' and as many columns as samples in the `ForestContainer`
+        #' and as many columns as dimensions in the leaves of trees in `ForestContainer`
         predict_raw_single_forest = function(forest_dataset, forest_num) {
             stopifnot(!is.null(forest_dataset$data_ptr))
             # Unpack dimensions
@@ -113,6 +113,21 @@ ForestSamples <- R6::R6Class(
             return(output)
         }, 
 
+        #' @description
+        #' Predict "raw" leaf values (without being multiplied by basis) for a specific tree in a specific forest on every observation in `forest_dataset`
+        #' @param forest_dataset `ForestDataset` R class
+        #' @param forest_num Index of the forest sample within the container
+        #' @param tree_num Index of the tree to be queried
+        #' @return matrix of predictions with as many rows as in `forest_dataset` 
+        #' and as many columns as dimensions in the leaves of trees in `ForestContainer`
+        predict_raw_single_tree = function(forest_dataset, forest_num, tree_num) {
+            stopifnot(!is.null(forest_dataset$data_ptr))
+
+            # Predict leaf values from forest
+            output <- predict_forest_raw_single_tree_cpp(self$forest_container_ptr, forest_dataset$data_ptr, forest_num, tree_num)
+            return(output)
+        }, 
+        
         #' @description
         #' Set a constant predicted value for every tree in the ensemble. 
         #' Stops program if any tree is more than a root node.