townforge/tests/unit_tests/rolling_median.cpp

214 lines
5.7 KiB
C++

// Copyright (c) 2019-2020, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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#include <random>
#include "gtest/gtest.h"
#include "misc_language.h"
#include "rolling_median.h"
#include "crypto/crypto.h"
TEST(rolling_median, one)
{
epee::misc_utils::rolling_median_t<uint64_t> m(1);
m.insert(42);
ASSERT_EQ(m.median(), 42);
m.insert(18);
ASSERT_EQ(m.median(), 18);
m.insert(7483);
ASSERT_EQ(m.median(), 7483);
}
TEST(rolling_median, two)
{
epee::misc_utils::rolling_median_t<uint64_t> m(2);
m.insert(42);
ASSERT_EQ(m.median(), 42);
m.insert(45);
ASSERT_EQ(m.median(), 43);
m.insert(49);
ASSERT_EQ(m.median(), 47);
m.insert(41);
ASSERT_EQ(m.median(), 45);
m.insert(43);
ASSERT_EQ(m.median(), 42);
m.insert(40);
ASSERT_EQ(m.median(), 41);
m.insert(41);
ASSERT_EQ(m.median(), 40);
}
TEST(rolling_median, series)
{
epee::misc_utils::rolling_median_t<uint64_t> m(100);
std::vector<uint64_t> v;
v.reserve(100);
for (int i = 0; i < 10000; ++i)
{
uint64_t r = crypto::rand<uint64_t>();
v.push_back(r);
if (v.size() > 100)
v.erase(v.begin());
m.insert(r);
std::vector<uint64_t> vcopy = v;
ASSERT_EQ(m.median(), epee::misc_utils::median(vcopy));
}
}
TEST(rolling_median, clear_whole)
{
epee::misc_utils::rolling_median_t<uint64_t> m(100);
std::vector<uint64_t> random, median;
random.reserve(10000);
median.reserve(10000);
for (int i = 0; i < 10000; ++i)
{
random.push_back(crypto::rand<uint64_t>());
m.insert(random.back());
median.push_back(m.median());
}
m.clear();
for (int i = 0; i < 10000; ++i)
{
m.insert(random[i]);
ASSERT_EQ(median[i], m.median());
}
}
TEST(rolling_median, clear_partway)
{
epee::misc_utils::rolling_median_t<uint64_t> m(100);
std::vector<uint64_t> random, median;
random.reserve(10000);
median.reserve(10000);
for (int i = 0; i < 10000; ++i)
{
random.push_back(crypto::rand<uint64_t>());
m.insert(random.back());
median.push_back(m.median());
}
m.clear();
for (int i = 10000 - 100; i < 10000; ++i)
{
m.insert(random[i]);
}
ASSERT_EQ(median[10000-1], m.median());
}
TEST(rolling_median, order)
{
epee::misc_utils::rolling_median_t<uint64_t> m(1000);
std::vector<uint64_t> random;
random.reserve(1000);
for (int i = 0; i < 1000; ++i)
{
random.push_back(crypto::rand<uint64_t>());
m.insert(random.back());
}
const uint64_t med = m.median();
std::sort(random.begin(), random.end(), [](uint64_t a, uint64_t b) { return a < b; });
m.clear();
for (int i = 0; i < 1000; ++i)
m.insert(random[i]);
ASSERT_EQ(med, m.median());
std::sort(random.begin(), random.end(), [](uint64_t a, uint64_t b) { return a > b; });
m.clear();
for (int i = 0; i < 1000; ++i)
m.insert(random[i]);
ASSERT_EQ(med, m.median());
std::shuffle(random.begin(), random.end(), crypto::random_device{});
m.clear();
for (int i = 0; i < 1000; ++i)
m.insert(random[i]);
ASSERT_EQ(med, m.median());
}
TEST(rolling_median, history_blind)
{
epee::misc_utils::rolling_median_t<uint64_t> m(10);
uint64_t median = 0;
for (int i = 0; i < 1000; ++i)
{
m.clear();
int history_length = 743723 % (i+1);
while (history_length--)
m.insert(743284 % (i+1));
for (int j = 0; j < 10; ++j)
m.insert(8924829384 % (j+1));
if (i == 0)
median = m.median();
else
ASSERT_EQ(median, m.median());
}
}
TEST(rolling_median, overflow)
{
epee::misc_utils::rolling_median_t<uint64_t> m(2);
uint64_t over_half = static_cast<uint64_t>(3) << static_cast<uint64_t>(62);
m.insert(over_half);
m.insert(over_half);
ASSERT_EQ((over_half + over_half) < over_half, true);
ASSERT_EQ(over_half, m.median());
}
TEST(rolling_median, size)
{
epee::misc_utils::rolling_median_t<uint64_t> m(10);
ASSERT_EQ(m.size(), 0);
m.insert(1);
ASSERT_EQ(m.size(), 1);
m.insert(2);
ASSERT_EQ(m.size(), 2);
m.clear();
ASSERT_EQ(m.size(), 0);
for (int i = 0; i < 10; ++i)
{
m.insert(80 % (i + 1));
ASSERT_EQ(m.size(), i + 1);
}
m.insert(1);
ASSERT_EQ(m.size(), 10);
m.insert(2);
ASSERT_EQ(m.size(), 10);
m.clear();
ASSERT_EQ(m.size(), 0);
m.insert(4);
ASSERT_EQ(m.size(), 1);
for (int i = 0; i < 1000; ++i)
{
m.insert(80 % (i + 1));
ASSERT_EQ(m.size(), std::min<int>(10, i + 2));
}
}