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- ///////////////////////////////////////////////////////////////////////////////
- // Copyright 2016 John Maddock. 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)
- #include <boost/multiprecision/cpp_bin_float.hpp>
- int main()
- {
- typedef boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<256> > ext_float_t;
- typedef boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<2046> > long_ext_float_t;
- ext_float_t x = 5e15;
- x += 0.5;
- ext_float_t x1 = x + 255.0 / (1 << 20); // + 2^-12 - eps
- ext_float_t x2 = x + 257.0 / (1 << 20); // + 2^-12 + eps
- double d1 = x1.convert_to<double>();
- double d2 = x2.convert_to<double>();
- std::cout << std::setprecision(18) << d1 << std::endl;
- std::cout << std::setprecision(18) << d2 << std::endl;
- x = 1e7 + 0.5;
- x1 = x + ldexp(255.0, -38); // + 2^-30 - eps
- x2 = x + ldexp(257.0, -38); // + 2^-30 + eps
- float f1 = x1.convert_to<float>();
- float f2 = x2.convert_to<float>();
- std::cout << std::setprecision(9) << f1 << std::endl;
- std::cout << std::setprecision(9) << f2 << std::endl;
- long_ext_float_t lf(1);
- lf += std::numeric_limits<long_ext_float_t>::epsilon();
- lf += std::numeric_limits<float>::epsilon() / 2;
- BOOST_ASSERT(lf != 1);
- float f3 = lf.convert_to<float>();
- std::cout << std::setprecision(9) << f3 << std::endl;
- return (d1 == d2) && (f1 == f2) && (f3 != 1) ? 0 : 1;
- }
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