random/test/test_discrete.cpp

124 lines
3.2 KiB
C++

/* test_poisson.cpp
*
* Copyright Steven Watanabe 2010
* Distributed under 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)
*
* $Id$
*
*/
#include <boost/random/discrete_distribution.hpp>
#include <boost/random/uniform_int.hpp>
#include <boost/random/mersenne_twister.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/exception/diagnostic_information.hpp>
#include <vector>
#include <iostream>
#include <numeric>
#include "chi_squared_test.hpp"
bool do_test(int n, long long max) {
std::cout << "running discrete(p0, p1, ..., p" << n-1 << ")" << " " << max << " times: " << std::flush;
std::vector<double> expected;
{
boost::mt19937 egen;
for(int i = 0; i < n; ++i) {
expected.push_back(egen());
}
double sum = std::accumulate(expected.begin(), expected.end(), 0.0);
for(std::vector<double>::iterator iter = expected.begin(), end = expected.end(); iter != end; ++iter) {
*iter /= sum;
}
}
boost::random::discrete_distribution<> dist(expected);
boost::mt19937 gen;
std::vector<long long> results(expected.size());
for(long long i = 0; i < max; ++i) {
++results[dist(gen)];
}
long long sum = std::accumulate(results.begin(), results.end(), 0ll);
if(sum != max) {
std::cout << "*** Failed: incorrect total: " << sum << " ***" << std::endl;
return false;
}
double chsqr = chi_squared_test(results, expected, max);
bool result = chsqr < 0.99;
const char* err = result? "" : "*";
std::cout << std::setprecision(17) << chsqr << err << std::endl;
std::cout << std::setprecision(6);
return result;
}
bool do_tests(int repeat, int max_n, long long trials) {
boost::mt19937 gen;
boost::uniform_int<> idist(1, max_n);
int errors = 0;
for(int i = 0; i < repeat; ++i) {
if(!do_test(idist(gen), trials)) {
++errors;
}
}
if(errors != 0) {
std::cout << "*** " << errors << " errors detected ***" << std::endl;
}
return errors == 0;
}
int usage() {
std::cerr << "Usage: test_discrete -r <repeat> -n <max n> -t <trials>" << std::endl;
return 2;
}
template<class T>
bool handle_option(int& argc, char**& argv, char opt, T& value) {
if(argv[0][1] == opt && argc > 1) {
--argc;
++argv;
value = boost::lexical_cast<T>(argv[0]);
return true;
} else {
return false;
}
}
int main(int argc, char** argv) {
int repeat = 10;
int max_n = 10000;
long long trials = 1000000ll;
if(argc > 0) {
--argc;
++argv;
}
while(argc > 0) {
if(argv[0][0] != '-') return usage();
else if(!handle_option(argc, argv, 'r', repeat)
&& !handle_option(argc, argv, 'n', max_n)
&& !handle_option(argc, argv, 't', trials)) {
return usage();
}
--argc;
++argv;
}
try {
if(do_tests(repeat, max_n, trials)) {
return 0;
} else {
return EXIT_FAILURE;
}
} catch(...) {
std::cerr << boost::current_exception_diagnostic_information() << std::endl;
return EXIT_FAILURE;
}
}