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 77