projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | // Copyright (c) 2007 John Maddock |
| 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_SIN_PI_HPP | |
| 7 | #define BOOST_MATH_SIN_PI_HPP | |
| 8 | ||
| 9 | #ifdef _MSC_VER | |
| 10 | #pragma once | |
| 11 | #endif | |
| 12 | ||
| 13 | #include <boost/config/no_tr1/cmath.hpp> | |
| 14 | #include <boost/math/tools/config.hpp> | |
| 15 | #include <boost/math/special_functions/math_fwd.hpp> | |
| 16 | #include <boost/math/special_functions/trunc.hpp> | |
| 17 | #include <boost/math/tools/promotion.hpp> | |
| 18 | #include <boost/math/constants/constants.hpp> | |
| 19 | ||
| 20 | namespace boost{ namespace math{ namespace detail{ | |
| 21 | ||
| 22 | template <class T, class Policy> | |
| 23 | T sin_pi_imp(T x, const Policy& pol) | |
| 24 | { | |
| 25 | BOOST_MATH_STD_USING // ADL of std names | |
| 26 | if(x < 0) | |
| 27 | return -sin_pi(-x); | |
| 28 | // sin of pi*x: | |
| 29 | bool invert; | |
| 30 | if(x < 0.5) | |
| 31 | return sin(constants::pi<T>() * x); | |
| 32 | if(x < 1) | |
| 33 | { | |
| 34 | invert = true; | |
| 35 | x = -x; | |
| 36 | } | |
| 37 | else | |
| 38 | invert = false; | |
| 39 | ||
| 40 | T rem = floor(x); | |
| 41 | if(itrunc(rem, pol) & 1) | |
| 42 | invert = !invert; | |
| 43 | rem = x - rem; | |
| 44 | if(rem > 0.5f) | |
| 45 | rem = 1 - rem; | |
| 46 | if(rem == 0.5f) | |
| 47 | return static_cast<T>(invert ? -1 : 1); | |
| 48 | ||
| 49 | rem = sin(constants::pi<T>() * rem); | |
| 50 | return invert ? T(-rem) : rem; | |
| 51 | } | |
| 52 | ||
| 53 | } // namespace detail | |
| 54 | ||
| 55 | template <class T, class Policy> | |
| 56 | inline typename tools::promote_args<T>::type sin_pi(T x, const Policy&) | |
| 57 | { | |
| 58 | typedef typename tools::promote_args<T>::type result_type; | |
| 59 | typedef typename policies::evaluation<result_type, Policy>::type value_type; | |
| 60 | typedef typename policies::normalise< | |
| 61 | Policy, | |
| 62 | policies::promote_float<false>, | |
| 63 | policies::promote_double<false>, | |
| 64 | policies::discrete_quantile<>, | |
| 65 | policies::assert_undefined<> >::type forwarding_policy; | |
| 66 | return policies::checked_narrowing_cast<result_type, forwarding_policy>(boost::math::detail::sin_pi_imp<value_type>(x, forwarding_policy()), "cos_pi"); | |
| 67 | } | |
| 68 | ||
| 69 | template <class T> | |
| 70 | inline typename tools::promote_args<T>::type sin_pi(T x) | |
| 71 | { | |
| 72 | return boost::math::sin_pi(x, policies::policy<>()); | |
| 73 | } | |
| 74 | ||
| 75 | } // namespace math | |
| 76 | } // namespace boost | |
| 77 | #endif | |
| 78 |