From f01edbc5c4d2393f5cf6ddc87d9e8cc14bb264bb Mon Sep 17 00:00:00 2001
From: Boris Gromov <0xff.root@gmail.com>
Date: Wed, 31 Jul 2024 10:04:45 +0200
Subject: [PATCH] Fix histogram indexing when accessed via operator [] (#939)

---
 include/etl/histogram.h | 4 ++--
 test/test_histogram.cpp | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/etl/histogram.h b/include/etl/histogram.h
index 15d54222a..ada532322 100644
--- a/include/etl/histogram.h
+++ b/include/etl/histogram.h
@@ -249,7 +249,7 @@ namespace etl
     //*********************************
     value_type operator [](key_type key) const
     {
-      return this->accumulator[key];
+      return this->accumulator[key - Start_Index];
     }
   };
 
@@ -373,7 +373,7 @@ namespace etl
     //*********************************
     value_type operator [](key_type key) const
     {
-      return this->accumulator[key];
+      return this->accumulator[key - start_index];
     }
 
   private:
diff --git a/test/test_histogram.cpp b/test/test_histogram.cpp
index 16c6373da..c682c723e 100644
--- a/test/test_histogram.cpp
+++ b/test/test_histogram.cpp
@@ -247,7 +247,7 @@ namespace
 
       for (size_t i = 0UL; i < output1.size(); ++i)
       {
-        CHECK_EQUAL(int(output1[i]), int(histogram[i]));
+        CHECK_EQUAL(int(output1[i]), int(histogram[i - 4]));
       }
     }