From 810e84d60d74a788c9ec4fa9aba6d7bba76a8319 Mon Sep 17 00:00:00 2001
From: vindex10 <vindex10@gmail.com>
Date: Fri, 30 Jul 2021 09:07:58 +0000
Subject: [PATCH] add test distributions mode benchmark

---
 .../performance/test_distributions_mode.cpp   | 74 +++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 reporting/performance/test_distributions_mode.cpp

diff --git a/reporting/performance/test_distributions_mode.cpp b/reporting/performance/test_distributions_mode.cpp
new file mode 100644
index 000000000..1bc4a77bf
--- /dev/null
+++ b/reporting/performance/test_distributions_mode.cpp
@@ -0,0 +1,74 @@
+//  (C) Copyright Victor Ananyev 2021.
+//  Use, modification and distribution are subject to the
+//  Boost Software License, Version 1.0. (See accompanying file
+//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#include <random>
+#include <vector>
+#include <boost/math/distributions.hpp>
+#include <benchmark/benchmark.h>
+
+
+template <class Z, template<typename> class dist >
+void test_mode_2param(benchmark::State& state)
+{
+    using boost::math::normal_distribution;
+
+    std::random_device rd;
+    std::mt19937_64 mt(rd());
+    std::normal_distribution<Z> noise(0., 1E-6);
+
+    for (auto _ : state)
+    {
+        state.PauseTiming();
+        Z p1 = state.range(0) + noise(mt);
+        Z p2 = state.range(1) + noise(mt);
+        dist<Z> the_dist(p1, p2);
+        state.ResumeTiming();
+        try {
+            benchmark::DoNotOptimize(mode(the_dist));
+        }
+        catch (boost::wrapexcept<boost::math::evaluation_error>& e) {
+            state.SkipWithError(e.what());
+            break;
+        }
+    }
+}
+
+
+template<class T>
+static void fixed_ratio_2args(benchmark::internal::Benchmark* b, T left_div_right, std::vector<int64_t> lefts) {
+    for (const T &left: lefts) {
+        b->Args({(int64_t)left, (int64_t)(left/left_div_right)});
+    }
+}
+
+
+using boost::math::non_central_chi_squared_distribution;
+
+BENCHMARK_TEMPLATE(test_mode_2param, long double, non_central_chi_squared_distribution)->ArgsProduct({
+    {2, 15, 50},
+    benchmark::CreateRange(4, 1024, /*multi=*/2)
+})->Name("fixed_k");
+
+BENCHMARK_TEMPLATE(test_mode_2param, long double, non_central_chi_squared_distribution)->ArgsProduct({
+    benchmark::CreateRange(4, 4096, /*multi=*/2),
+    {0, 30, 100, 500}
+})->Name("fixed_nc");
+
+BENCHMARK_TEMPLATE(test_mode_2param, long double, non_central_chi_squared_distribution)
+    -> Apply([](benchmark::internal::Benchmark*b) {
+                fixed_ratio_2args<long double>(b, 0.05L, benchmark::CreateRange(4, 4096, /*multi=*/2));
+    }) -> Name("fixed_scale_0_05");
+
+BENCHMARK_TEMPLATE(test_mode_2param, long double, non_central_chi_squared_distribution)
+    -> Apply([](benchmark::internal::Benchmark*b) {
+                fixed_ratio_2args<long double>(b, 0.15L, benchmark::CreateRange(4, 4096, /*multi=*/2));
+    }) -> Name("fixed_scale_0_15");
+
+BENCHMARK_TEMPLATE(test_mode_2param, long double, non_central_chi_squared_distribution)
+    -> Apply([](benchmark::internal::Benchmark*b) {
+                fixed_ratio_2args<long double>(b, 0.25L, benchmark::CreateRange(4, 4096, /*multi=*/2));
+    }) -> Name("fixed_scale_0_25");
+
+BENCHMARK_MAIN();