From a059fd44a0bed65943b63eb1dc8d0fcb1175fc23 Mon Sep 17 00:00:00 2001
From: Sebastian Eibl <sebastian.eibl@mpcdf.mpg.de>
Date: Tue, 18 Feb 2025 10:29:08 +0100
Subject: [PATCH] fix and test getBin

---
 mrmd/data/MultiHistogram.hpp      | 2 +-
 mrmd/data/MultiHistogram.test.cpp | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/mrmd/data/MultiHistogram.hpp b/mrmd/data/MultiHistogram.hpp
index cc86390..99c8910 100644
--- a/mrmd/data/MultiHistogram.hpp
+++ b/mrmd/data/MultiHistogram.hpp
@@ -56,7 +56,7 @@ struct MultiHistogram
      */
     KOKKOS_INLINE_FUNCTION idx_t getBin(const real_t& val) const
     {
-        auto bin = idx_c((val - min) * inverseBinSize);
+        auto bin = idx_c(std::floor((val - min) * inverseBinSize));
         if (bin < 0) bin = -1;
         if (bin >= numBins) bin = -1;
         return bin;
diff --git a/mrmd/data/MultiHistogram.test.cpp b/mrmd/data/MultiHistogram.test.cpp
index 9a1eb4d..0f11cff 100644
--- a/mrmd/data/MultiHistogram.test.cpp
+++ b/mrmd/data/MultiHistogram.test.cpp
@@ -21,6 +21,15 @@ namespace mrmd
 namespace data
 {
 
+TEST(MultiHistogram, getBin)
+{
+    MultiHistogram histogram("histogram", 0_r, 10_r, 10, 2);
+    EXPECT_EQ(histogram.getBin(-0.5_r), -1);
+    EXPECT_EQ(histogram.getBin(0.5_r), 0);
+    EXPECT_EQ(histogram.getBin(5.5_r), 5);
+    EXPECT_EQ(histogram.getBin(10.5_r), -1);
+}
+
 TEST(MultiHistogram, getBinPosition)
 {
     MultiHistogram histogram("histogram", 0_r, 10_r, 10, 2);