diff --git a/include/aare/ClusterVector.hpp b/include/aare/ClusterVector.hpp
index 22315cc..fef3f07 100644
--- a/include/aare/ClusterVector.hpp
+++ b/include/aare/ClusterVector.hpp
@@ -297,7 +297,7 @@ class ClusterVector<Cluster<T, ClusterSizeX, ClusterSizeY, CoordType>> {
      * @param frame_number frame number of the clusters. Default is 0, which is
      * also used to indicate that the clusters come from many frames
      */
-    ClusterVector(size_t capacity = 300, uint64_t frame_number = 0)
+    ClusterVector(size_t capacity = 300, int32_t frame_number = 0)
         : m_frame_number(frame_number) {
         m_data.reserve(capacity);
     }
diff --git a/src/CalculateEta.test.cpp b/src/CalculateEta.test.cpp
index 2bdf387..52109e8 100644
--- a/src/CalculateEta.test.cpp
+++ b/src/CalculateEta.test.cpp
@@ -37,16 +37,6 @@ auto get_test_parameters() {
             Eta2<int>{3. / 5, 4. / 6, 1, 11}));
 }
 
-TEST_CASE("compute_largest_2x2_subcluster", "[.eta_calculation]") {
-    auto [cluster, expected_eta] = get_test_parameters();
-
-    auto [sum, index] = std::visit(
-        [](const auto &clustertype) { return clustertype.max_sum_2x2(); },
-        cluster);
-    CHECK(expected_eta.c == index);
-    CHECK(expected_eta.sum == sum);
-}
-
 TEST_CASE("calculate_eta2", "[.eta_calculation]") {
 
     auto [cluster, expected_eta] = get_test_parameters();
diff --git a/src/Cluster.test.cpp b/src/Cluster.test.cpp
index e502012..07e269a 100644
--- a/src/Cluster.test.cpp
+++ b/src/Cluster.test.cpp
@@ -26,3 +26,49 @@ TEST_CASE("Correct Instantiation of Cluster and ClusterVector",
     CHECK(not is_cluster_v<int>);
     CHECK(is_cluster_v<Cluster<int, 3, 3>>);
 }
+<<<<<<< Updated upstream
+=======
+
+using ClusterTypes =
+    std::variant<Cluster<int, 2, 2>, Cluster<int, 3, 3>, Cluster<int, 5, 5>,
+                 Cluster<int, 4, 2>, Cluster<int, 2, 3>>;
+
+auto get_test_sum_parameters() {
+    return GENERATE(
+        std::make_tuple(ClusterTypes{Cluster<int, 2, 2>{0, 0, {1, 2, 3, 1}}},
+                        std::make_pair(7, 0)),
+        std::make_tuple(
+            ClusterTypes{Cluster<int, 3, 3>{0, 0, {1, 2, 3, 4, 5, 6, 1, 2, 7}}},
+            std::make_pair(20, 3)),
+        std::make_tuple(ClusterTypes{Cluster<int, 5, 5>{
+                            0, 0, {1, 6, 7, 6, 5, 4, 3, 2, 1, 8, 8, 9, 2,
+                                   1, 4, 5, 6, 7, 8, 4, 1, 1, 1, 1, 1}}},
+                        std::make_pair(28, 8)),
+        std::make_tuple(
+            ClusterTypes{Cluster<int, 4, 2>{0, 0, {1, 4, 7, 2, 5, 6, 4, 3}}},
+            std::make_pair(21, 1)),
+        std::make_tuple(
+            ClusterTypes{Cluster<int, 2, 3>{0, 0, {1, 3, 2, 3, 4, 2}}},
+            std::make_pair(11, 1)));
+}
+
+TEST_CASE("compute_largest_2x2_subcluster", "[.cluster]") {
+    auto [cluster, sum_pair] = get_test_sum_parameters();
+
+    auto sum = std::visit(
+        [](const auto &clustertype) { return clustertype.max_sum_2x2(); },
+        cluster);
+    CHECK(sum_pair.first == sum.first);
+    CHECK(sum_pair.second == sum.second);
+}
+
+TEST_CASE("Test sum of Cluster", "[.cluster]") {
+    Cluster<int, 2, 2> cluster{0, 0, {1, 2, 3, 4}};
+
+    CHECK(cluster.sum() == 10);
+
+    Cluster<int, 2, 3> cluster2x3{0, 0, {1, 3, 2, 3, 4, 2}};
+
+    CHECK(cluster2x3.sum() == 15);
+}
+>>>>>>> Stashed changes
diff --git a/src/ClusterVector.test.cpp b/src/ClusterVector.test.cpp
index 5a5abe0..8ceba1a 100644
--- a/src/ClusterVector.test.cpp
+++ b/src/ClusterVector.test.cpp
@@ -30,6 +30,21 @@ TEST_CASE("item_size return the size of the cluster stored"){
     using C4 = Cluster<char, 10, 5>;
     ClusterVector<C4> cv4(4);
     CHECK(cv4.item_size() == sizeof(C4));
+<<<<<<< Updated upstream
+=======
+
+    using C5 = Cluster<int32_t, 2, 3>;
+    ClusterVector<C5> cv5(4);
+    CHECK(cv5.item_size() == sizeof(C5));
+
+    using C6 = Cluster<double, 5, 5>;
+    ClusterVector<C6> cv6(4);
+    CHECK(cv6.item_size() == sizeof(C6)); // double uses padding!!!
+
+    using C7 = Cluster<double, 3, 3>;
+    ClusterVector<C7> cv7(4);
+    CHECK(cv7.item_size() == sizeof(C7));
+>>>>>>> Stashed changes
 }
 
 TEST_CASE("ClusterVector 2x2 int32_t capacity 4, push back then read",
@@ -211,6 +226,32 @@ TEST_CASE("Concatenate two cluster vectors where we need to allocate",
     REQUIRE(ptr[3].y == 17);
 }
 
+TEST_CASE("calculate cluster sum", "[.ClusterVector]") {
+    ClusterVector<Cluster<int32_t, 2, 2>> cv1(2);
+    Cluster<int32_t, 2, 2> c1 = {1, 2, {3, 4, 5, 6}};
+    cv1.push_back(c1);
+    Cluster<int32_t, 2, 2> c2 = {6, 7, {8, 9, 10, 11}};
+    cv1.push_back(c2);
+
+    auto sum1 = cv1.sum();
+
+    std::vector<int32_t> expected_sum1{18, 38};
+
+    CHECK(sum1 == expected_sum1);
+
+    ClusterVector<Cluster<int32_t, 3, 3>> cv2(2);
+    Cluster<int32_t, 3, 3> c3 = {1, 2, {3, 4, 5, 6, 1, 7, 8, 1, 1}};
+    cv2.push_back(c3);
+    Cluster<int32_t, 3, 3> c4 = {6, 7, {8, 9, 10, 11, 13, 5, 12, 2, 4}};
+    cv2.push_back(c4);
+
+    auto sum2 = cv2.sum();
+
+    std::vector<int32_t> expected_sum2{36, 74};
+
+    CHECK(sum2 == expected_sum2);
+}
+
 struct ClusterTestData {
     uint8_t ClusterSizeX;
     uint8_t ClusterSizeY;