// Copyright (C) 2006 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#include <sstream>
#include <string>
#include <cstdlib>
#include <ctime>
#include <cmath>
#include <dlib/rand.h>
#include <dlib/compress_stream.h>
#include <dlib/hash.h>
#include <dlib/statistics.h>
#include "tester.h"
namespace
{
using namespace test;
using namespace dlib;
using namespace std;
logger dlog("test.rand");
void check_bpp (
const std::string str
)
{
istringstream rdata;
ostringstream sout;
rdata.str(str);
double compressed_size;
compress_stream::kernel_1a cs1;
compress_stream::kernel_2a cs2;
compress_stream_kernel_1<
entropy_encoder_model_kernel_5<257,entropy_encoder::kernel_1a,4000000,4>,
entropy_decoder_model_kernel_5<257,entropy_decoder::kernel_1a,4000000,4>,
crc32::kernel_1a
> cs3;
print_spinner();
rdata.clear();
rdata.seekg(0);
sout.clear();
sout.str("");
cs1.compress(rdata,sout);
compressed_size = sout.str().size();
compressed_size *= 8;
compressed_size /= str.size();
DLIB_TEST_MSG(compressed_size >= 8, "order 0 bps: " << compressed_size);
dlog << LINFO << "order 0: " << compressed_size;
print_spinner();
rdata.clear();
rdata.seekg(0);
sout.clear();
sout.str("");
cs2.compress(rdata,sout);
compressed_size = sout.str().size();
compressed_size *= 8;
compressed_size /= str.size();
DLIB_TEST_MSG(compressed_size >= 8, "order 1 bps: " << compressed_size);
dlog << LINFO << "order 1: " << compressed_size;
print_spinner();
rdata.clear();
rdata.seekg(0);
sout.clear();
sout.str("");
cs3.compress(rdata,sout);
compressed_size = sout.str().size();
compressed_size *= 8;
compressed_size /= str.size();
DLIB_TEST_MSG(compressed_size >= 8, "order 4 bps: " << compressed_size);
dlog << LINFO << "order 4: " << compressed_size;
}
template <
typename rand
>
void rand_test (
)
/*!
requires
- rand is an implementation of rand/rand_kernel_abstract.h
is instantiated with int
ensures
- runs tests on rand for compliance with the specs
!*/
{
ostringstream seed;
seed << (unsigned int)time(0);
ostringstream sout;
rand r, r2;
DLIB_TEST(r.get_seed() == "");
r.set_seed(seed.str());
DLIB_TEST(r.get_seed() == seed.str());
r.clear();
DLIB_TEST(r.get_seed() == "");
swap(r,r2);
DLIB_TEST(r.get_seed() == "");
r.set_seed(seed.str());
DLIB_TEST(r.get_seed() == seed.str());
swap(r,r2);
DLIB_TEST(r2.get_seed() == seed.str());
DLIB_TEST(r.get_seed() == "");
swap(r,r2);
DLIB_TEST(r.get_seed() == seed.str());
DLIB_TEST(r2.get_seed() == "");
print_spinner();
unsigned long size = 100000;
for (unsigned long i = 0; i < size; ++i)
{
uint32 ch = r.get_random_32bit_number();
sout.write((char*)&ch,4);
}
check_bpp(sout.str());
sout.clear();
sout.str("");
print_spinner();
for (unsigned long i = 0; i < size; ++i)
{
uint16 ch = r.get_random_16bit_number();
sout.write((char*)&ch,2);
}
check_bpp(sout.str());
sout.clear();
sout.str("");
print_spinner();
for (unsigned long i = 0; i < size; ++i)
{
unsigned char ch = r.get_random_8bit_number();
sout.write((char*)&ch,1);
}
check_bpp(sout.str());
sout.clear();
sout.str("");
// make sure the things can serialize right
{
r.clear();
r2.clear();
for (int i =0; i < 1000; ++i)
{
r.get_random_32bit_number();
r.get_random_gaussian();
}
ostringstream sout;
serialize(r, sout);
istringstream sin(sout.str());
deserialize(r2, sin);
for (int i =0; i < 1000; ++i)
{
DLIB_TEST(r.get_random_32bit_number() == r2.get_random_32bit_number());
DLIB_TEST(std::abs(r.get_random_gaussian() - r2.get_random_gaussian()) < 1e-14);
}
}
// make sure calling clear() and set_seed("") do the same thing
{
r.clear();
r2.set_seed("");
rand r3;
DLIB_TEST(r.get_seed() == r2.get_seed());
DLIB_TEST(r.get_seed() == r3.get_seed());
for (int i =0; i < 1000; ++i)
{
const uint32 num1 = r.get_random_32bit_number();
const uint32 num2 = r2.get_random_32bit_number();
const uint32 num3 = r3.get_random_32bit_number();
DLIB_TEST( num1 == num2);
DLIB_TEST( num1 == num3);
}
}
}
template <typename rand_type>
void test_normal_numbers(
rand_type& rnd
)
{
print_spinner();
dlog << LINFO << "test normality";
double cnt1 = 0; // num <= -1.2
double cnt2 = 0; // num <= -0.5
double cnt3 = 0; // num <= 0
double cnt4 = 0; // num <= 0.5
double cnt5 = 0; // num <= 1.2
const unsigned long total = 1000000;
for (unsigned long i = 0; i < total; ++i)
{
const double r = rnd.get_random_gaussian();
if (r <= -1.2) cnt1 += 1;
if (r <= -0.5) cnt2 += 1;
if (r <= 0) cnt3 += 1;
if (r <= 0.5) cnt4 += 1;
if (r <= 1.2) cnt5 += 1;
}
cnt1 /= total;
cnt2 /= total;
cnt3 /= total;
cnt4 /= total;
cnt5 /= total;
dlog << LINFO << "cnt1: "<< cnt1;
dlog << LINFO << "cnt2: "<< cnt2;
dlog << LINFO << "cnt3: "<< cnt3;
dlog << LINFO << "cnt4: "<< cnt4;
dlog << LINFO << "cnt5: "<< cnt5;
DLIB_TEST(std::abs(cnt1 - 0.11507) < 0.001);
DLIB_TEST(std::abs(cnt2 - 0.30854) < 0.001);
DLIB_TEST(std::abs(cnt3 - 0.5) < 0.001);
DLIB_TEST(std::abs(cnt4 - 0.69146) < 0.001);
DLIB_TEST(std::abs(cnt5 - 0.88493) < 0.001);
}
void test_gaussian_random_hash()
{
print_spinner();
dlog << LINFO << "test_gaussian_random_hash()";
double cnt1 = 0; // num <= -1.2
double cnt2 = 0; // num <= -0.5
double cnt3 = 0; // num <= 0
double cnt4 = 0; // num <= 0.5
double cnt5 = 0; // num <= 1.2
const unsigned long total = 1000000;
for (unsigned long i = 0; i < total; ++i)
{
const double r = gaussian_random_hash(i,0,0);
if (r <= -1.2) cnt1 += 1;
if (r <= -0.5) cnt2 += 1;
if (r <= 0) cnt3 += 1;
if (r <= 0.5) cnt4 += 1;
if (r <= 1.2) cnt5 += 1;
}
for (unsigned long i = 0; i < total; ++i)
{
const double r = gaussian_random_hash(0,i,0);
if (r <= -1.2) cnt1 += 1;
if (r <= -0.5) cnt2 += 1;
if (r <= 0) cnt3 += 1;
if (r <= 0.5) cnt4 += 1;
if (r <= 1.2) cnt5 += 1;
}
for (unsigned long i = 0; i < total; ++i)
{
const double r = gaussian_random_hash(0,0,i);
if (r <= -1.2) cnt1 += 1;
if (r <= -0.5) cnt2 += 1;
if (r <= 0) cnt3 += 1;
if (r <= 0.5) cnt4 += 1;
if (r <= 1.2) cnt5 += 1;
}
cnt1 /= total*3;
cnt2 /= total*3;
cnt3 /= total*3;
cnt4 /= total*3;
cnt5 /= total*3;
dlog << LINFO << "cnt1: "<< cnt1;
dlog << LINFO << "cnt2: "<< cnt2;
dlog << LINFO << "cnt3: "<< cnt3;
dlog << LINFO << "cnt4: "<< cnt4;
dlog << LINFO << "cnt5: "<< cnt5;
DLIB_TEST(std::abs(cnt1 - 0.11507) < 0.001);
DLIB_TEST(std::abs(cnt2 - 0.30854) < 0.001);
DLIB_TEST(std::abs(cnt3 - 0.5) < 0.001);
DLIB_TEST(std::abs(cnt4 - 0.69146) < 0.001);
DLIB_TEST(std::abs(cnt5 - 0.88493) < 0.001);
}
void test_uniform_random_hash()
{
print_spinner();
dlog << LINFO << "test_uniform_random_hash()";
double cnt1 = 0; // num <= 0.2
double cnt2 = 0; // num <= 0.4
double cnt3 = 0; // num <= 0.6
double cnt4 = 0; // num <= 0.8
double cnt5 = 0; // num <= 1.0
double min_val = 10;
double max_val = 0;
const unsigned long total = 1000000;
for (unsigned long i = 0; i < total; ++i)
{
const double r = uniform_random_hash(i,0,0);
min_val = min(r,min_val);
max_val = max(r,max_val);
if (r <= 0.2) cnt1 += 1;
if (r <= 0.4) cnt2 += 1;
if (r <= 0.6) cnt3 += 1;
if (r <= 0.8) cnt4 += 1;
if (r <= 1.0) cnt5 += 1;
}
for (unsigned long i = 0; i < total; ++i)
{
const double r = uniform_random_hash(0,i,0);
min_val = min(r,min_val);
max_val = max(r,max_val);
if (r <= 0.2) cnt1 += 1;
if (r <= 0.4) cnt2 += 1;
if (r <= 0.6) cnt3 += 1;
if (r <= 0.8) cnt4 += 1;
if (r <= 1.0) cnt5 += 1;
}
for (unsigned long i = 0; i < total; ++i)
{
const double r = uniform_random_hash(0,0,i);
min_val = min(r,min_val);
max_val = max(r,max_val);
if (r <= 0.2) cnt1 += 1;
if (r <= 0.4) cnt2 += 1;
if (r <= 0.6) cnt3 += 1;
if (r <= 0.8) cnt4 += 1;
if (r <= 1.0) cnt5 += 1;
}
cnt1 /= total*3;
cnt2 /= total*3;
cnt3 /= total*3;
cnt4 /= total*3;
cnt5 /= total*3;
dlog << LINFO << "cnt1: "<< cnt1;
dlog << LINFO << "cnt2: "<< cnt2;
dlog << LINFO << "cnt3: "<< cnt3;
dlog << LINFO << "cnt4: "<< cnt4;
dlog << LINFO << "cnt5: "<< cnt5;
dlog << LINFO << "min_val: "<< min_val;
dlog << LINFO << "max_val: "<< max_val;
DLIB_TEST(std::abs(cnt1 - 0.2) < 0.001);
DLIB_TEST(std::abs(cnt2 - 0.4) < 0.001);
DLIB_TEST(std::abs(cnt3 - 0.6) < 0.001);
DLIB_TEST(std::abs(cnt4 - 0.8) < 0.001);
DLIB_TEST(std::abs(cnt5 - 1.0) < 0.001);
DLIB_TEST(std::abs(min_val - 0.0) < 0.001);
DLIB_TEST(std::abs(max_val - 1.0) < 0.001);
}
void test_get_integer()
{
print_spinner();
dlib::rand rnd;
int big_val = 0;
int small_val = 0;
const long long maxval = (((unsigned long long)1)<<62) + (((unsigned long long)1)<<61);
for (int i = 0; i < 10000000; ++i)
{
if (rnd.get_integer(maxval) > maxval/2)
++big_val;
else
++small_val;
}
// make sure there isn't any funny bias
DLIB_TEST(std::abs(big_val/(double)small_val - 1) < 0.001);
//cout << big_val/(double)small_val << endl;
}
void test_weibull_distribution()
{
print_spinner();
dlib::rand rnd(0);
const size_t N = 1024*1024*4;
const double tol = 0.01;
double k=1.0, lambda=2.0, g=6.0;
dlib::running_stats<double> stats;
for (size_t i = 0; i < N; i++)
stats.add(rnd.get_random_weibull(lambda, k, g));
double expected_mean = g + lambda*std::tgamma(1 + 1.0 / k);
double expected_var = lambda*lambda*(std::tgamma(1 + 2.0 / k) - std::pow(std::tgamma(1 + 1.0 / k),2));
DLIB_TEST(std::abs(stats.mean() - expected_mean) < tol);
DLIB_TEST(std::abs(stats.variance() - expected_var) < tol);
}
void test_exponential_distribution()
{
print_spinner();
dlib::rand rnd(0);
const size_t N = 1024*1024*5;
const double lambda = 1.5;
print_spinner();
dlib::running_stats<double> stats;
for (size_t i = 0; i < N; i++)
stats.add(rnd.get_random_exponential(lambda));
DLIB_TEST(std::abs(stats.mean() - 1.0 / lambda) < 0.001);
DLIB_TEST(std::abs(stats.variance() - 1.0 / (lambda*lambda)) < 0.001);
DLIB_TEST(std::abs(stats.skewness() - 2.0) < 0.01);
DLIB_TEST(std::abs(stats.ex_kurtosis() - 6.0) < 0.1);
}
void test_beta_distribution()
{
print_spinner();
dlib::rand rnd(0);
const size_t N = 1024*1024*5;
const double a = 0.2;
const double b = 1.5;
running_stats<double> stats;
for (size_t i = 0; i < N; i++)
stats.add(rnd.get_random_beta(a, b));
const double expected_mean = a / (a + b);
const double expected_var = a * b / (std::pow(a + b, 2) * (a + b + 1));
DLIB_TEST(std::abs(stats.mean() - expected_mean) < 1e-5);
DLIB_TEST(std::abs(stats.variance() - expected_var) < 1e-5);
}
void outputs_are_not_changed()
{
// dlib::rand has been around a really long time and it is a near certainty that there is
// client code that depends on dlib::rand yielding the exact random sequence it happens to
// yield for any given seed. So we test that the output values of dlib::rand are not
// changed in this test.
{
dlib::rand rnd;
std::vector<uint32> out;
for (int i = 0; i < 30; ++i) {
out.push_back(rnd.get_random_32bit_number());
}
const std::vector<uint32> expected = {
725333953,251387296,3200466189,2466988778,2049276419,2620437198,2806522923,
2922190659,4151412029,2894696296,1344442829,1165961100,328304965,1533685458,
3399102146,3995382051,1569312238,2353373514,2512982725,2903494783,787425157,
699798098,330364342,2870851082,659976556,1726343583,3551405331,3171822159,
1292599360,955731010};
DLIB_TEST(out == expected);
}
{
dlib::rand rnd;
rnd.set_seed("this seed");
std::vector<uint32> out;
for (int i = 0; i < 30; ++i) {
out.push_back(rnd.get_random_32bit_number());
}
const std::vector<uint32> expected = {
856663397,2356564049,1192662566,3478257893,1069117227,
1922448468,497418632,2504525324,987414451,769612124,77224022,2998161761,
1364481427,639342008,1778351952,1931573847,3213816676,3019312695,4179936779,
3637269252,4279821094,3738954922,3651625265,3159592157,333323775,4075800582,
4237631248,357468843,483435718,1255945812};
DLIB_TEST(out == expected);
}
{
dlib::rand rnd;
rnd.set_seed("some other seed");
std::vector<int> out;
for (int i = 0; i < 30; ++i) {
out.push_back(rnd.get_integer(1000));
}
const std::vector<int> expected = {
243,556,158,256,772,84,837,920,767,769,939,394,121,367,575,877,861,506,
451,845,870,638,825,516,327,25,646,373,386,227};
DLIB_TEST(out == expected);
}
}
class rand_tester : public tester
{
public:
rand_tester (
) :
tester ("test_rand",
"Runs tests on the rand component.")
{}
void perform_test (
)
{
dlog << LINFO << "testing kernel_1a";
outputs_are_not_changed();
rand_test<dlib::rand>();
rand_test<dlib::rand>();
dlib::rand rnd;
test_normal_numbers(rnd);
test_gaussian_random_hash();
test_uniform_random_hash();
test_get_integer();
test_weibull_distribution();
test_exponential_distribution();
test_beta_distribution();
}
} a;
}