43 lines
1.6 KiB
C++
43 lines
1.6 KiB
C++
///////////////////////////////////////////////////////////////
|
|
// Copyright 2013 John Maddock. Distributed under the Boost
|
|
// Software License, Version 1.0. (See accompanying file
|
|
// LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt
|
|
|
|
//[float128_eg
|
|
#include <boost/multiprecision/float128.hpp>
|
|
#include <boost/math/special_functions/gamma.hpp>
|
|
#include <iostream>
|
|
|
|
int main()
|
|
{
|
|
using namespace boost::multiprecision;
|
|
|
|
// Operations at 128-bit precision and full numeric_limits support:
|
|
float128 b = 2;
|
|
// There are 113-bits of precision:
|
|
std::cout << std::numeric_limits<float128>::digits << std::endl;
|
|
// Or 34 decimal places:
|
|
std::cout << std::numeric_limits<float128>::digits10 << std::endl;
|
|
// We can use any C++ std lib function, lets print all the digits as well:
|
|
std::cout << std::setprecision(std::numeric_limits<float128>::max_digits10)
|
|
<< log(b) << std::endl; // print log(2) = 0.693147180559945309417232121458176575
|
|
// We can also use any function from Boost.Math:
|
|
std::cout << boost::math::tgamma(b) << std::endl;
|
|
// And since we have an extended exponent range we can generate some really large
|
|
// numbers here (4.02387260077093773543702433923004111e+2564):
|
|
std::cout << boost::math::tgamma(float128(1000)) << std::endl;
|
|
//
|
|
// We can declare constants using GCC or Intel's native types, and the Q suffix,
|
|
// these can be declared constexpr if required:
|
|
/*<-*/
|
|
#ifndef BOOST_NO_CXX11_CONSTEXPR
|
|
/*->*/
|
|
constexpr float128 pi = 3.1415926535897932384626433832795028841971693993751058Q;
|
|
/*<-*/
|
|
#endif
|
|
/*->*/
|
|
return 0;
|
|
}
|
|
//]
|
|
|