multiprecision/test/test_float_io.cpp

374 lines
13 KiB
C++

// Copyright John Maddock 2011.
// 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)
#ifdef _MSC_VER
#define _SCL_SECURE_NO_WARNINGS
#endif
#if !defined(TEST_MPF_50) && !defined(TEST_CPP_DEC_FLOAT) && !defined(TEST_MPFR_50) && !defined(TEST_MPFI_50) && !defined(TEST_FLOAT128)
#define TEST_MPF_50
#define TEST_CPP_DEC_FLOAT
#define TEST_MPFR_50
#define TEST_MPFI_50
#define TEST_FLOAT128
#ifdef _MSC_VER
#pragma message("CAUTION!!: No backend type specified so testing everything.... this will take some time!!")
#endif
#ifdef __GNUC__
#pragma warning "CAUTION!!: No backend type specified so testing everything.... this will take some time!!"
#endif
#endif
#if defined(TEST_MPF_50)
#include <boost/multiprecision/gmp.hpp>
#endif
#if defined(TEST_MPFR_50)
#include <boost/multiprecision/mpfr.hpp>
#endif
#if defined(TEST_MPFI_50)
#include <boost/multiprecision/mpfi.hpp>
#endif
#ifdef TEST_CPP_DEC_FLOAT
#include <boost/multiprecision/cpp_dec_float.hpp>
#endif
#ifdef TEST_FLOAT128
#include <boost/multiprecision/float128.hpp>
#endif
#include <boost/random/mersenne_twister.hpp>
#include <boost/random/uniform_int.hpp>
#include "test.hpp"
#include <boost/array.hpp>
#include <iostream>
#include <iomanip>
#ifdef BOOST_MSVC
#pragma warning(disable : 4127)
#endif
#if defined(TEST_MPF_50)
template <unsigned N, boost::multiprecision::expression_template_option ET>
bool has_bad_bankers_rounding(const boost::multiprecision::number<boost::multiprecision::gmp_float<N>, ET>&)
{
return true;
}
#endif
#if defined(TEST_FLOAT128) && defined(BOOST_INTEL)
bool has_bad_bankers_rounding(const boost::multiprecision::float128&)
{
return true;
}
#endif
template <class T>
bool has_bad_bankers_rounding(const T&)
{
return false;
}
bool is_bankers_rounding_error(const std::string& s, const char* expect)
{
// This check isn't foolproof: that would require *much* more sophisticated code!!!
std::string::size_type l = std::strlen(expect);
if (l != s.size())
return false;
std::string::size_type len = s.find('e');
if (len == std::string::npos)
len = l - 1;
else
--len;
if (s.compare(0, len, expect, len))
return false;
if (s[len] != expect[len] + 1)
return false;
return true;
}
void print_flags(std::ios_base::fmtflags f)
{
std::cout << "Formatting flags were: ";
if (f & std::ios_base::scientific)
std::cout << "scientific ";
if (f & std::ios_base::fixed)
std::cout << "fixed ";
if (f & std::ios_base::showpoint)
std::cout << "showpoint ";
if (f & std::ios_base::showpos)
std::cout << "showpos ";
std::cout << std::endl;
}
template <class T>
void test()
{
typedef T mp_t;
boost::array<std::ios_base::fmtflags, 9> f =
{{std::ios_base::fmtflags(0), std::ios_base::showpoint, std::ios_base::showpos, std::ios_base::scientific, std::ios_base::scientific | std::ios_base::showpos,
std::ios_base::scientific | std::ios_base::showpoint, std::ios_base::fixed, std::ios_base::fixed | std::ios_base::showpoint,
std::ios_base::fixed | std::ios_base::showpos}};
boost::array<boost::array<const char*, 13 * 9>, 40> string_data = {{
#include "libs/multiprecision/test/string_data.ipp"
}};
double num = 123456789.0;
double denom = 1;
double val = num;
for (unsigned j = 0; j < 40; ++j)
{
unsigned col = 0;
for (unsigned prec = 1; prec < 14; ++prec)
{
for (unsigned i = 0; i < f.size(); ++i, ++col)
{
std::stringstream ss;
ss.precision(prec);
ss.flags(f[i]);
ss << mp_t(val);
const char* expect = string_data[j][col];
if (ss.str() != expect)
{
if (has_bad_bankers_rounding(mp_t()) && is_bankers_rounding_error(ss.str(), expect))
{
std::cout << "Ignoring bankers-rounding error with GMP mp_f.\n";
}
else
{
std::cout << std::setprecision(20) << "Testing value " << val << std::endl;
print_flags(f[i]);
std::cout << "Precision is: " << prec << std::endl;
std::cout << "Got: " << ss.str() << std::endl;
std::cout << "Expected: " << expect << std::endl;
++boost::detail::test_errors();
mp_t(val).str(prec, f[i]); // for debugging
}
}
}
}
num = -num;
if (j & 1)
denom *= 8;
val = num / denom;
}
boost::array<const char*, 13 * 9> zeros =
{{"0", "0.", "+0", "0.0e+00", "+0.0e+00", "0.0e+00", "0.0", "0.0", "+0.0", "0", "0.0", "+0", "0.00e+00", "+0.00e+00", "0.00e+00", "0.00", "0.00", "+0.00", "0", "0.00", "+0", "0.000e+00", "+0.000e+00", "0.000e+00", "0.000", "0.000", "+0.000", "0", "0.000", "+0", "0.0000e+00", "+0.0000e+00", "0.0000e+00", "0.0000", "0.0000", "+0.0000", "0", "0.0000", "+0", "0.00000e+00", "+0.00000e+00", "0.00000e+00", "0.00000", "0.00000", "+0.00000", "0", "0.00000", "+0", "0.000000e+00", "+0.000000e+00", "0.000000e+00", "0.000000", "0.000000", "+0.000000", "0", "0.000000", "+0", "0.0000000e+00", "+0.0000000e+00", "0.0000000e+00", "0.0000000", "0.0000000", "+0.0000000", "0", "0.0000000", "+0", "0.00000000e+00", "+0.00000000e+00", "0.00000000e+00", "0.00000000", "0.00000000", "+0.00000000", "0", "0.00000000", "+0", "0.000000000e+00", "+0.000000000e+00", "0.000000000e+00", "0.000000000", "0.000000000", "+0.000000000", "0", "0.000000000", "+0", "0.0000000000e+00", "+0.0000000000e+00", "0.0000000000e+00", "0.0000000000", "0.0000000000", "+0.0000000000", "0", "0.0000000000", "+0", "0.00000000000e+00", "+0.00000000000e+00", "0.00000000000e+00", "0.00000000000", "0.00000000000", "+0.00000000000", "0", "0.00000000000", "+0", "0.000000000000e+00", "+0.000000000000e+00", "0.000000000000e+00", "0.000000000000", "0.000000000000", "+0.000000000000", "0", "0.000000000000", "+0", "0.0000000000000e+00", "+0.0000000000000e+00", "0.0000000000000e+00", "0.0000000000000", "0.0000000000000", "+0.0000000000000"}};
unsigned col = 0;
val = 0;
for (unsigned prec = 1; prec < 14; ++prec)
{
for (unsigned i = 0; i < f.size(); ++i, ++col)
{
std::stringstream ss;
ss.precision(prec);
ss.flags(f[i]);
ss << mp_t(val);
const char* expect = zeros[col];
if (ss.str() != expect)
{
std::cout << std::setprecision(20) << "Testing value " << val << std::endl;
print_flags(f[i]);
std::cout << "Precision is: " << prec << std::endl;
std::cout << "Got: " << ss.str() << std::endl;
std::cout << "Expected: " << expect << std::endl;
++boost::detail::test_errors();
mp_t(val).str(prec, f[i]); // for debugging
}
}
}
if (std::numeric_limits<mp_t>::has_infinity)
{
T val = std::numeric_limits<T>::infinity();
BOOST_CHECK_EQUAL(val.str(), "inf");
BOOST_CHECK_EQUAL(val.str(0, std::ios_base::showpos), "+inf");
val = -val;
BOOST_CHECK_EQUAL(val.str(), "-inf");
BOOST_CHECK_EQUAL(val.str(0, std::ios_base::showpos), "-inf");
val = static_cast<T>("inf");
BOOST_CHECK_EQUAL(val, std::numeric_limits<T>::infinity());
val = static_cast<T>("+inf");
BOOST_CHECK_EQUAL(val, std::numeric_limits<T>::infinity());
val = static_cast<T>("-inf");
BOOST_CHECK_EQUAL(val, -std::numeric_limits<T>::infinity());
}
if (std::numeric_limits<mp_t>::has_quiet_NaN)
{
T val = std::numeric_limits<T>::quiet_NaN();
BOOST_CHECK_EQUAL(val.str(), "nan");
val = static_cast<T>("nan");
BOOST_CHECK((boost::math::isnan)(val));
}
//
// Bug cases:
//
// https://github.com/boostorg/multiprecision/issues/113
//
{
T val("99.9809");
BOOST_CHECK_EQUAL(val.str(3, std::ios_base::fixed), "99.981");
}
}
template <class T>
T generate_random()
{
typedef typename T::backend_type::exponent_type e_type;
static boost::random::mt19937 gen;
T val = gen();
T prev_val = -1;
while (val != prev_val)
{
val *= (gen.max)();
prev_val = val;
val += gen();
}
e_type e;
val = frexp(val, &e);
static boost::random::uniform_int_distribution<e_type> ui(0, std::numeric_limits<T>::max_exponent - 10);
return ldexp(val, ui(gen));
}
template <class T>
struct max_digits10_proxy
{
static const unsigned value = std::numeric_limits<T>::digits10 + 5;
};
#ifdef TEST_CPP_DEC_FLOAT
template <unsigned D, boost::multiprecision::expression_template_option ET>
struct max_digits10_proxy<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<D>, ET> >
{
static const unsigned value = std::numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<D>, ET> >::max_digits10;
};
#endif
#ifdef TEST_MPF_50
template <unsigned D, boost::multiprecision::expression_template_option ET>
struct max_digits10_proxy<boost::multiprecision::number<boost::multiprecision::gmp_float<D>, ET> >
{
static const unsigned value = std::numeric_limits<boost::multiprecision::number<boost::multiprecision::gmp_float<D>, ET> >::max_digits10;
};
#endif
#ifdef TEST_MPFR_50
template <unsigned D, boost::multiprecision::expression_template_option ET>
struct max_digits10_proxy<boost::multiprecision::number<boost::multiprecision::mpfr_float_backend<D>, ET> >
{
static const unsigned value = std::numeric_limits<boost::multiprecision::number<boost::multiprecision::mpfr_float_backend<D>, ET> >::max_digits10;
};
#endif
template <class T>
void do_round_trip(const T& val, std::ios_base::fmtflags f)
{
std::stringstream ss;
#ifndef BOOST_NO_CXX11_NUMERIC_LIMITS
ss << std::setprecision(std::numeric_limits<T>::max_digits10);
#else
ss << std::setprecision(max_digits10_proxy<T>::value);
#endif
ss.flags(f);
ss << val;
T new_val = static_cast<T>(ss.str());
BOOST_CHECK_EQUAL(new_val, val);
new_val = static_cast<T>(val.str(0, f));
BOOST_CHECK_EQUAL(new_val, val);
}
template <class T>
void do_round_trip(const T& val)
{
do_round_trip(val, std::ios_base::fmtflags(0));
do_round_trip(val, std::ios_base::fmtflags(std::ios_base::scientific));
if ((fabs(val) > 1) && (fabs(val) < 1e100))
do_round_trip(val, std::ios_base::fmtflags(std::ios_base::fixed));
}
template <class T>
void test_round_trip()
{
for (unsigned i = 0; i < 1000; ++i)
{
T val = generate_random<T>();
do_round_trip(val);
do_round_trip(T(-val));
do_round_trip(T(1 / val));
do_round_trip(T(-1 / val));
}
}
#ifdef TEST_FLOAT128
void test_hexadecimal_floating_point()
{
using boost::multiprecision::float128;
float128 x = 0x1p+0Q;
std::string s = x.str(0, std::ios_base::fmtflags(std::ios_base::fixed | std::ios_base::scientific));
BOOST_CHECK_EQUAL(s, "0x1p+0");
s = x.str(0, std::ios_base::fmtflags(std::ios_base::floatfield));
BOOST_CHECK_EQUAL(s, "0x1p+0");
x = -1;
s = x.str(0, std::ios_base::fmtflags(std::ios_base::floatfield));
BOOST_CHECK_EQUAL(s, "-0x1p+0");
// hexadecimal representation of pi; test a round trip:
float128 pi1 = 0x1.921fb54442d18469898cc51701b8p+1Q;
s = pi1.str(0, std::ios_base::fmtflags(std::ios_base::floatfield));
float128 pi2(s);
BOOST_CHECK_EQUAL(pi1, pi2);
}
#endif
int main()
{
#ifdef TEST_MPFR_50
test<boost::multiprecision::mpfr_float_50>();
test<boost::multiprecision::mpfr_float_100>();
test_round_trip<boost::multiprecision::mpfr_float_50>();
test_round_trip<boost::multiprecision::mpfr_float_100>();
#endif
#ifdef TEST_MPFI_50
test<boost::multiprecision::mpfr_float_50>();
test<boost::multiprecision::mpfr_float_100>();
test_round_trip<boost::multiprecision::mpfr_float_50>();
test_round_trip<boost::multiprecision::mpfr_float_100>();
#endif
#ifdef TEST_CPP_DEC_FLOAT
test<boost::multiprecision::cpp_dec_float_50>();
test<boost::multiprecision::cpp_dec_float_100>();
// cpp_dec_float has extra guard digits that messes this up:
test_round_trip<boost::multiprecision::cpp_dec_float_50>();
test_round_trip<boost::multiprecision::cpp_dec_float_100>();
#endif
#ifdef TEST_MPF_50
test<boost::multiprecision::mpf_float_50>();
test<boost::multiprecision::mpf_float_100>();
/*
// I can't get this to work with mpf_t - mpf_str appears
// not to actually print enough decimal digits:
test_round_trip<boost::multiprecision::mpf_float_50>();
test_round_trip<boost::multiprecision::mpf_float_100>();
*/
#endif
#ifdef TEST_FLOAT128
test<boost::multiprecision::float128>();
test_hexadecimal_floating_point();
#ifndef BOOST_INTEL
test_round_trip<boost::multiprecision::float128>();
#endif
#endif
return boost::report_errors();
}