ceph/src/boost/libs/math/include_private/boost/math/constants/generate.hpp

   1 //  Copyright John Maddock 2010.
   2 //  Use, modification and distribution are subject to the
   3 //  Boost Software License, Version 1.0. (See accompanying file
   4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_MATH_CONSTANTS_GENERATE_INCLUDED
   7 #define BOOST_MATH_CONSTANTS_GENERATE_INCLUDED
   8
   9 #include <boost/math/constants/constants.hpp>
  10 #include <boost/regex.hpp>
  11 #include <iostream>
  12 #include <iomanip>
  13 #include <sstream>
  14
  15 #ifdef USE_MPFR
  16 #include <boost/math/bindings/mpfr.hpp>
  17 #elif defined(USE_MPREAL)
  18 #include <boost/math/bindings/mpreal.hpp>
  19 #elif defined(USE_CPP_FLOAT)
  20 #include <boost/multiprecision/cpp_dec_float.hpp>
  21 #else
  22 #include <boost/math/bindings/rr.hpp>
  23 #endif
  24
  25 namespace boost{ namespace math{ namespace constants{
  26
  27 #ifdef USE_MPFR
  28 typedef mpfr_class generator_type;
  29 #elif defined(USE_MPREAL)
  30 typedef mpfr::mpreal generator_type;
  31 #elif defined(USE_CPP_FLOAT)
  32 typedef boost::multiprecision::number<boost::multiprecision::cpp_dec_float<500> > generator_type;
  33 #else
  34 typedef ntl::RR generator_type;
  35 #endif
  36
  37 inline void print_constant(const char* name, generator_type(*f)(const mpl::int_<0>&))
  38 {
  39 #ifdef USE_MPFR
  40    mpfr_class::set_dprec(((200 + 1) * 1000L) / 301L);
  41 #elif defined(USE_MPREAL)
  42    mpfr::mpreal::set_default_prec(((200 + 1) * 1000L) / 301L);
  43 #elif defined(USE_CPP_FLOAT)
  44    // Nothing to do, precision is already set.
  45 #else
  46    ntl::RR::SetPrecision(((200 + 1) * 1000L) / 301L);
  47    ntl::RR::SetOutputPrecision(102);
  48 #endif
  49    generator_type value = f(boost::mpl::int_<0>());
  50    std::stringstream os;
  51    os << std::setprecision(110) << std::scientific;
  52    os << value;
  53    std::string s = os.str();
  54    static const regex e("([+-]?\\d+(?:\\.\\d{0,36})?)(\\d*)(?:e([+-]?\\d+))?");
  55    smatch what;
  56    if(regex_match(s, what, e))
  57    {
  58       std::cout <<
  59          "BOOST_DEFINE_MATH_CONSTANT(" << name << ", "
  60          << what[1] << "e" << (what[3].length() ? what[3].str() : std::string("0")) << ", "
  61          << "\"" << what[1] << what[2] << "e" << (what[3].length() ? what[3].str() : std::string("0"))
  62          << "\");" << std::endl;
  63    }
  64    else
  65    {
  66       std::cout << "Format of numeric constant was not recognised!!" << std::endl;
  67    }
  68 }
  69
  70 #define BOOST_CONSTANTS_GENERATE(name) \
  71    boost::math::constants::print_constant(#name, \
  72    & boost::math::constants::detail::BOOST_JOIN(constant_, name)<boost::math::constants::generator_type>::get)
  73
  74 }}} // namespaces
  75
  76 #endif // BOOST_MATH_CONSTANTS_GENERATE_INCLUDED