Chris@16: /* Boost interval/constants.hpp template implementation file
Chris@16:  *
Chris@16:  * Copyright 2002 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
Chris@16:  *
Chris@16:  * Distributed under the Boost Software License, Version 1.0.
Chris@16:  * (See accompanying file LICENSE_1_0.txt or
Chris@16:  * copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16:  */
Chris@16: 
Chris@16: #ifndef BOOST_NUMERIC_INTERVAL_CONSTANTS_HPP
Chris@16: #define BOOST_NUMERIC_INTERVAL_CONSTANTS_HPP
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace numeric {
Chris@16: namespace interval_lib {
Chris@16: namespace constants {
Chris@16: 
Chris@16: // These constants should be exactly computed.
Chris@16: // Decimal representations wouldn't do it since the standard doesn't
Chris@16: // specify the rounding (even nearest) that should be used.
Chris@16: 
Chris@16: static const float pi_f_l = 13176794.0f/(1<<22);
Chris@16: static const float pi_f_u = 13176795.0f/(1<<22);
Chris@16: static const double pi_d_l = (3373259426.0 + 273688.0 / (1<<21)) / (1<<30);
Chris@16: static const double pi_d_u = (3373259426.0 + 273689.0 / (1<<21)) / (1<<30);
Chris@16: 
Chris@16: template<class T> inline T pi_lower() { return 3; }
Chris@16: template<class T> inline T pi_upper() { return 4; }
Chris@16: template<class T> inline T pi_half_lower() { return 1; }
Chris@16: template<class T> inline T pi_half_upper() { return 2; }
Chris@16: template<class T> inline T pi_twice_lower() { return 6; }
Chris@16: template<class T> inline T pi_twice_upper() { return 7; }
Chris@16: 
Chris@16: template<> inline float pi_lower<float>() { return pi_f_l; }
Chris@16: template<> inline float pi_upper<float>() { return pi_f_u; }
Chris@16: template<> inline float pi_half_lower<float>() { return pi_f_l / 2; }
Chris@16: template<> inline float pi_half_upper<float>() { return pi_f_u / 2; }
Chris@16: template<> inline float pi_twice_lower<float>() { return pi_f_l * 2; }
Chris@16: template<> inline float pi_twice_upper<float>() { return pi_f_u * 2; }
Chris@16: 
Chris@16: template<> inline double pi_lower<double>() { return pi_d_l; }
Chris@16: template<> inline double pi_upper<double>() { return pi_d_u; }
Chris@16: template<> inline double pi_half_lower<double>() { return pi_d_l / 2; }
Chris@16: template<> inline double pi_half_upper<double>() { return pi_d_u / 2; }
Chris@16: template<> inline double pi_twice_lower<double>() { return pi_d_l * 2; }
Chris@16: template<> inline double pi_twice_upper<double>() { return pi_d_u * 2; }
Chris@16: 
Chris@16: template<> inline long double pi_lower<long double>() { return pi_d_l; }
Chris@16: template<> inline long double pi_upper<long double>() { return pi_d_u; }
Chris@16: template<> inline long double pi_half_lower<long double>() { return pi_d_l / 2; }
Chris@16: template<> inline long double pi_half_upper<long double>() { return pi_d_u / 2; }
Chris@16: template<> inline long double pi_twice_lower<long double>() { return pi_d_l * 2; }
Chris@16: template<> inline long double pi_twice_upper<long double>() { return pi_d_u * 2; }
Chris@16: 
Chris@16: } // namespace constants
Chris@16: 
Chris@16: template<class I> inline
Chris@16: I pi()
Chris@16: {
Chris@16:   typedef typename I::base_type T;
Chris@16:   return I(constants::pi_lower<T>(),
Chris@16:            constants::pi_upper<T>(), true);
Chris@16: }
Chris@16: 
Chris@16: template<class I> inline
Chris@16: I pi_half()
Chris@16: {
Chris@16:   typedef typename I::base_type T;
Chris@16:   return I(constants::pi_half_lower<T>(),
Chris@16:            constants::pi_half_upper<T>(), true);
Chris@16: }
Chris@16: 
Chris@16: template<class I> inline
Chris@16: I pi_twice()
Chris@16: {
Chris@16:   typedef typename I::base_type T;
Chris@16:   return I(constants::pi_twice_lower<T>(),
Chris@16:            constants::pi_twice_upper<T>(), true);
Chris@16: }
Chris@16: 
Chris@16: } // namespace interval_lib
Chris@16: } // namespace numeric
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif // BOOST_NUMERIC_INTERVAL_CONSTANTS_HPP