sl@0: /* Boost interval/constants.hpp template implementation file
sl@0:  *
sl@0:  * Copyright 2002 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
sl@0:  *
sl@0:  * Distributed under the Boost Software License, Version 1.0.
sl@0:  * (See accompanying file LICENSE_1_0.txt or
sl@0:  * copy at http://www.boost.org/LICENSE_1_0.txt)
sl@0:  */
sl@0: 
sl@0: #ifndef BOOST_NUMERIC_INTERVAL_CONSTANTS_HPP
sl@0: #define BOOST_NUMERIC_INTERVAL_CONSTANTS_HPP
sl@0: 
sl@0: namespace boost {
sl@0: namespace numeric {
sl@0: namespace interval_lib {
sl@0: namespace constants {
sl@0: 
sl@0: // These constants should be exactly computed.
sl@0: // Decimal representations wouldn't do it since the standard doesn't
sl@0: // specify the rounding (even nearest) that should be used.
sl@0: 
sl@0: static const float pi_f_l = 13176794.0f/(1<<22);
sl@0: static const float pi_f_u = 13176795.0f/(1<<22);
sl@0: static const double pi_d_l = (3373259426.0 + 273688.0 / (1<<21)) / (1<<30);
sl@0: static const double pi_d_u = (3373259426.0 + 273689.0 / (1<<21)) / (1<<30);
sl@0: 
sl@0: template<class T> inline T pi_lower() { return 3; }
sl@0: template<class T> inline T pi_upper() { return 4; }
sl@0: template<class T> inline T pi_half_lower() { return 1; }
sl@0: template<class T> inline T pi_half_upper() { return 2; }
sl@0: template<class T> inline T pi_twice_lower() { return 6; }
sl@0: template<class T> inline T pi_twice_upper() { return 7; }
sl@0: 
sl@0: template<> inline float pi_lower<float>() { return pi_f_l; }
sl@0: template<> inline float pi_upper<float>() { return pi_f_u; }
sl@0: template<> inline float pi_half_lower<float>() { return pi_f_l / 2; }
sl@0: template<> inline float pi_half_upper<float>() { return pi_f_u / 2; }
sl@0: template<> inline float pi_twice_lower<float>() { return pi_f_l * 2; }
sl@0: template<> inline float pi_twice_upper<float>() { return pi_f_u * 2; }
sl@0: 
sl@0: template<> inline double pi_lower<double>() { return pi_d_l; }
sl@0: template<> inline double pi_upper<double>() { return pi_d_u; }
sl@0: template<> inline double pi_half_lower<double>() { return pi_d_l / 2; }
sl@0: template<> inline double pi_half_upper<double>() { return pi_d_u / 2; }
sl@0: template<> inline double pi_twice_lower<double>() { return pi_d_l * 2; }
sl@0: template<> inline double pi_twice_upper<double>() { return pi_d_u * 2; }
sl@0: 
sl@0: template<> inline long double pi_lower<long double>() { return pi_d_l; }
sl@0: template<> inline long double pi_upper<long double>() { return pi_d_u; }
sl@0: template<> inline long double pi_half_lower<long double>() { return pi_d_l / 2; }
sl@0: template<> inline long double pi_half_upper<long double>() { return pi_d_u / 2; }
sl@0: template<> inline long double pi_twice_lower<long double>() { return pi_d_l * 2; }
sl@0: template<> inline long double pi_twice_upper<long double>() { return pi_d_u * 2; }
sl@0: 
sl@0: } // namespace constants
sl@0: 
sl@0: template<class I> inline
sl@0: I pi()
sl@0: {
sl@0:   typedef typename I::base_type T;
sl@0:   return I(constants::pi_lower<T>(),
sl@0:            constants::pi_upper<T>(), true);
sl@0: }
sl@0: 
sl@0: template<class I> inline
sl@0: I pi_half()
sl@0: {
sl@0:   typedef typename I::base_type T;
sl@0:   return I(constants::pi_half_lower<T>(),
sl@0:            constants::pi_half_upper<T>(), true);
sl@0: }
sl@0: 
sl@0: template<class I> inline
sl@0: I pi_twice()
sl@0: {
sl@0:   typedef typename I::base_type T;
sl@0:   return I(constants::pi_twice_lower<T>(),
sl@0:            constants::pi_twice_upper<T>(), true);
sl@0: }
sl@0: 
sl@0: } // namespace interval_lib
sl@0: } // namespace numeric
sl@0: } // namespace boost
sl@0: 
sl@0: #endif // BOOST_NUMERIC_INTERVAL_CONSTANTS_HPP