ceph/src/boost/libs/multiprecision/example/cpp_bin_float_snips.cpp

   1 ///////////////////////////////////////////////////////////////
   2 //  Copyright 2013 John Maddock. Distributed under the Boost
   3 //  Software License, Version 1.0. (See accompanying file
   4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_
   5
   6 //[cpp_bin_float_eg
   7 #include <boost/multiprecision/cpp_bin_float.hpp>
   8 #include <boost/math/special_functions/gamma.hpp>
   9 #include <iostream>
  10
  11 int main()
  12 {
  13    using namespace boost::multiprecision;
  14
  15    // Operations at fixed precision and full numeric_limits support:
  16    cpp_bin_float_100 b = 2;
  17    std::cout << std::numeric_limits<cpp_bin_float_100>::digits << std::endl;
  18    std::cout << std::numeric_limits<cpp_bin_float_100>::digits10 << std::endl;
  19    // We can use any C++ std lib function, lets print all the digits as well:
  20    std::cout << std::setprecision(std::numeric_limits<cpp_bin_float_100>::max_digits10)
  21       << log(b) << std::endl; // print log(2)
  22    // We can also use any function from Boost.Math:
  23    std::cout << boost::math::tgamma(b) << std::endl;
  24    // These even work when the argument is an expression template:
  25    std::cout << boost::math::tgamma(b * b) << std::endl;
  26    // And since we have an extended exponent range we can generate some really large
  27    // numbers here (4.0238726007709377354370243e+2564):
  28    std::cout << boost::math::tgamma(cpp_bin_float_100(1000)) << std::endl;
  29    return 0;
  30 }
  31
  32 //]