math/test/test_difference.cpp
2019-08-10 08:50:12 -04:00

162 lines
6.9 KiB
C++

// (C) Copyright John Maddock 2015.
// 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 <boost/math/concepts/real_concept.hpp>
#define BOOST_TEST_MAIN
#include <boost/test/unit_test.hpp>
#include <boost/test/tools/floating_point_comparison.hpp>
#include <boost/math/special_functions/next.hpp>
#include <boost/math/special_functions/ulp.hpp>
#include <boost/math/special_functions/relative_difference.hpp>
#include <iostream>
#include <iomanip>
template <class T>
void test_value(const T& val, const char* name)
{
using namespace boost::math;
using std::fabs;
T next = float_next(val);
T prev = float_prior(val);
if((boost::math::isinf)(next))
{
BOOST_CHECK_EQUAL(relative_difference(val, next), tools::max_value<T>());
return;
}
if((boost::math::isinf)(prev))
{
BOOST_CHECK_EQUAL(relative_difference(val, prev), tools::max_value<T>());
return;
}
BOOST_CHECK_EQUAL(relative_difference(val, next), relative_difference(next, val));
BOOST_CHECK_EQUAL(epsilon_difference(val, next), epsilon_difference(next, val));
BOOST_CHECK_LE(relative_difference(val, next), boost::math::tools::epsilon<T>());
BOOST_CHECK_LE(epsilon_difference(val, next), T(1));
if((fabs(val) > tools::min_value<T>()) || (fabs(next) > tools::min_value<T>()))
{
BOOST_CHECK_GT(relative_difference(val, next), T(0));
BOOST_CHECK_GT(epsilon_difference(val, next), T(0));
}
else
{
BOOST_CHECK_EQUAL(relative_difference(val, next), T(0));
BOOST_CHECK_EQUAL(epsilon_difference(val, next), T(0));
}
BOOST_CHECK_EQUAL(relative_difference(val, prev), relative_difference(prev, val));
BOOST_CHECK_EQUAL(epsilon_difference(val, prev), epsilon_difference(prev, val));
if((fabs(val) > tools::min_value<T>()) || (fabs(prev) > tools::min_value<T>()))
{
BOOST_CHECK_GT(relative_difference(val, prev), T(0));
BOOST_CHECK_GT(epsilon_difference(val, prev), T(0));
}
else
{
BOOST_CHECK_EQUAL(relative_difference(val, prev), T(0));
BOOST_CHECK_EQUAL(epsilon_difference(val, prev), T(0));
}
}
template <class T>
void test_values(const T& val, const char* name)
{
static const T a = static_cast<T>(1.3456724e22);
static const T b = static_cast<T>(1.3456724e-22);
static const T z = 0;
static const T one = 1;
static const T two = 2;
std::cout << "Testing type " << name << std::endl;
T den = (std::numeric_limits<T>::min)() / 4;
if(den != 0)
{
std::cout << "Denormals are active\n";
}
else
{
std::cout << "Denormals are flushed to zero.\n";
}
test_value(a, name);
test_value(-a, name);
test_value(b, name);
test_value(-b, name);
test_value(boost::math::tools::epsilon<T>(), name);
test_value(-boost::math::tools::epsilon<T>(), name);
test_value(boost::math::tools::min_value<T>(), name);
test_value(-boost::math::tools::min_value<T>(), name);
if (std::numeric_limits<T>::is_specialized && (std::numeric_limits<T>::has_denorm == std::denorm_present) && ((std::numeric_limits<T>::min)() / 2 != 0))
{
test_value(z, name);
test_value(-z, name);
}
test_value(one, name);
test_value(-one, name);
test_value(two, name);
test_value(-two, name);
static const int primes[] = {
11, 13, 17, 19, 23, 29,
31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
73, 79, 83, 89, 97, 101, 103, 107, 109, 113,
127, 131, 137, 139, 149, 151, 157, 163, 167, 173,
179, 181, 191, 193, 197, 199, 211, 223, 227, 229,
233, 239, 241, 251, 257, 263, 269, 271, 277, 281,
283, 293, 307, 311, 313, 317, 331, 337, 347, 349,
353, 359, 367, 373, 379, 383, 389, 397, 401, 409,
419, 421, 431, 433, 439, 443, 449, 457, 461, 463,
};
for(unsigned i = 0; i < sizeof(primes) / sizeof(primes[0]); ++i)
{
for(unsigned j = 0; j < sizeof(primes) / sizeof(primes[0]); ++j)
{
test_value(T(primes[i]) / T(primes[j]), name);
test_value(-T(primes[i]) / T(primes[j]), name);
}
}
using namespace boost::math;
BOOST_CHECK_EQUAL(relative_difference(tools::min_value<T>(), -tools::min_value<T>()), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(tools::min_value<T>(), -tools::min_value<T>()), tools::max_value<T>());
if(std::numeric_limits<T>::has_infinity)
{
BOOST_CHECK_EQUAL(relative_difference(std::numeric_limits<T>::infinity(), std::numeric_limits<T>::infinity()), T(0));
BOOST_CHECK_EQUAL(epsilon_difference(std::numeric_limits<T>::infinity(), std::numeric_limits<T>::infinity()), T(0));
BOOST_CHECK_EQUAL(relative_difference(std::numeric_limits<T>::infinity(), tools::max_value<T>()), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(std::numeric_limits<T>::infinity(), tools::max_value<T>()), tools::max_value<T>());
BOOST_CHECK_EQUAL(relative_difference(std::numeric_limits<T>::infinity(), tools::max_value<T>() / 2), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(std::numeric_limits<T>::infinity(), tools::max_value<T>() / 2), tools::max_value<T>());
BOOST_CHECK_EQUAL(relative_difference(tools::max_value<T>(), std::numeric_limits<T>::infinity()), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(tools::max_value<T>(), std::numeric_limits<T>::infinity()), tools::max_value<T>());
BOOST_CHECK_EQUAL(relative_difference(tools::max_value<T>() / 2, std::numeric_limits<T>::infinity()), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(tools::max_value<T>() / 2, std::numeric_limits<T>::infinity()), tools::max_value<T>());
}
if(std::numeric_limits<T>::has_quiet_NaN)
{
BOOST_CHECK_EQUAL(relative_difference(std::numeric_limits<T>::quiet_NaN(), std::numeric_limits<T>::quiet_NaN()), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(std::numeric_limits<T>::quiet_NaN(), std::numeric_limits<T>::quiet_NaN()), tools::max_value<T>());
BOOST_CHECK_EQUAL(relative_difference(std::numeric_limits<T>::quiet_NaN(), T(2)), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(std::numeric_limits<T>::quiet_NaN(), T(2)), tools::max_value<T>());
BOOST_CHECK_EQUAL(relative_difference(T(2), std::numeric_limits<T>::quiet_NaN()), tools::max_value<T>());
BOOST_CHECK_EQUAL(epsilon_difference(T(2), std::numeric_limits<T>::quiet_NaN()), tools::max_value<T>());
}
}
BOOST_AUTO_TEST_CASE( test_main )
{
test_values(1.0f, "float");
test_values(1.0, "double");
#ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
test_values(1.0L, "long double");
test_values(boost::math::concepts::real_concept(0), "real_concept");
#endif
}