From e45d3eb7dfeb5e5f6a41768a83d8a03d8ec1ec2f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fran=C3=A7ois-David=20Collin?=
 <Francois-David.Collin@umontpellier.fr>
Date: Thu, 27 Aug 2020 12:37:56 +0200
Subject: [PATCH] Bug in oob error rate vs number of trees result

---
 src/ForestOnline.cpp               | 4 ++++
 src/ForestOnline.hpp               | 2 +-
 src/ForestOnlineClassification.cpp | 6 ++++--
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/ForestOnline.cpp b/src/ForestOnline.cpp
index 69e6942..7729b52 100644
--- a/src/ForestOnline.cpp
+++ b/src/ForestOnline.cpp
@@ -135,6 +135,9 @@ void ForestOnline::init(std::string dependent_variable_name, MemoryMode memory_m
   if (!prediction_mode && order_snps) {
     data->orderSnpLevels(dependent_variable_name, (importance_mode == IMP_GINI_CORRECTED));
   }
+
+  tree_order = std::vector<size_t>(num_trees);
+
 }
 
 void ForestOnline::run(bool verbose, bool compute_oob_error) {
@@ -602,6 +605,7 @@ void ForestOnline::growTreesInThread(uint thread_idx, std::vector<double>* varia
       trees[i]->predict(predict_data,false);
       predictInternal(i);
       mutex.lock();
+      tree_order[progress] = i;
       ++progress;
       if (verbose_out) {
         #ifdef PYTHON_OUTPUT
diff --git a/src/ForestOnline.hpp b/src/ForestOnline.hpp
index c017c5a..466b53a 100644
--- a/src/ForestOnline.hpp
+++ b/src/ForestOnline.hpp
@@ -181,7 +181,7 @@ class ForestOnline {
   PredictionType prediction_type;
   uint num_random_splits;
   uint max_depth;
-
+  std::vector<size_t> tree_order;
   // MAXSTAT splitrule
   double alpha;
   double minprop;
diff --git a/src/ForestOnlineClassification.cpp b/src/ForestOnlineClassification.cpp
index 71d4bc7..baae0b7 100644
--- a/src/ForestOnlineClassification.cpp
+++ b/src/ForestOnlineClassification.cpp
@@ -172,7 +172,7 @@ void ForestOnlineClassification::calculateAfterGrow(size_t tree_idx, bool oob) {
         mutex_post.lock();
         ++class_counts[sampleID][res];
         mutex_post.unlock();
-        if (!class_counts[sample_idx].empty())
+        if (!class_counts[sampleID].empty())
           to_add += (mostFrequentValue(class_counts[sampleID], random_number_generator) == data->get(sampleID,dependent_varID)) ? 0.0 : 1.0;
       }
       predictions[2][0][tree_idx] += to_add/static_cast<double>(numOOB);
@@ -237,7 +237,9 @@ void ForestOnlineClassification::computePredictionErrorInternal()
     for(auto sample_idx = 0; sample_idx < predict_data->getNumRows(); sample_idx++) {
       predictions[1][0][sample_idx] = mostFrequentValue(class_count[sample_idx], random_number_generator);
     }
-
+  std::vector<double> sort_oob_trees(num_trees);
+  for(auto i = 0; i < num_trees; i++) sort_oob_trees[i] = predictions[2][0][tree_order[i]];
+  predictions[2][0] = sort_oob_trees;
 }
 
 // #nocov start