added benchmark to time generalize calculate_eta - twice as long so will keep specific version for 2x2 and 3x3 clusters

benchmarks/calculateeta_benchmark.cpp

@@ -0,0 +1,66 @@
+#include "aare/ClusterFile.hpp"
+#include <benchmark/benchmark.h>
+
+using namespace aare;
+
+class ClusterFixture : public benchmark::Fixture {
+  public:
+    Cluster<int, 2, 2> cluster_2x2{};
+    Cluster<int, 3, 3> cluster_3x3{};
+
+    void SetUp(::benchmark::State &state) {
+        int temp_data[4] = {1, 2, 3, 1};
+        std::copy(std::begin(temp_data), std::end(temp_data),
+                  std::begin(cluster_2x2.data));
+
+        cluster_2x2.x = 0;
+        cluster_2x2.y = 0;
+
+        int temp_data2[9] = {1, 2, 3, 1, 3, 4, 5, 1, 20};
+        std::copy(std::begin(temp_data2), std::end(temp_data2),
+                  std::begin(cluster_3x3.data));
+
+        cluster_3x3.x = 0;
+        cluster_3x3.y = 0;
+    }
+
+    // void TearDown(::benchmark::State& state) {
+    // }
+};
+
+BENCHMARK_F(ClusterFixture, Calculate2x2Eta)(benchmark::State &st) {
+    for (auto _ : st) {
+        // This code gets timed
+        Eta2 eta = calculate_eta2(cluster_2x2);
+        benchmark::DoNotOptimize(eta);
+    }
+}
+
+// almost takes double the time
+BENCHMARK_F(ClusterFixture,
+            CalculateGeneralEtaFor2x2Cluster)(benchmark::State &st) {
+    for (auto _ : st) {
+        // This code gets timed
+        Eta2 eta = calculate_eta2<int, 2, 2>(cluster_2x2);
+        benchmark::DoNotOptimize(eta);
+    }
+}
+
+BENCHMARK_F(ClusterFixture, Calculate3x3Eta)(benchmark::State &st) {
+    for (auto _ : st) {
+        // This code gets timed
+        Eta2 eta = calculate_eta2(cluster_3x3);
+        benchmark::DoNotOptimize(eta);
+    }
+}
+
+// almost takes double the time
+BENCHMARK_F(ClusterFixture,
+            CalculateGeneralEtaFor3x3Cluster)(benchmark::State &st) {
+    for (auto _ : st) {
+        // This code gets timed
+        Eta2 eta = calculate_eta2<int, 3, 3>(cluster_3x3);
+        benchmark::DoNotOptimize(eta);
+    }
+}
+// BENCHMARK_MAIN();