| |
| // (C) Copyright John Maddock 2006. |
| // Use, modification and distribution are subject to the |
| // Boost Software License, Version 1.0. (See accompanying file |
| // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| |
| #ifndef BOOST_MATH_SPECIAL_HERMITE_HPP |
| #define BOOST_MATH_SPECIAL_HERMITE_HPP |
| |
| #ifdef _MSC_VER |
| #pragma once |
| #endif |
| |
| #include <boost/math/special_functions/math_fwd.hpp> |
| #include <boost/math/tools/config.hpp> |
| #include <boost/math/policies/error_handling.hpp> |
| |
| namespace boost{ |
| namespace math{ |
| |
| // Recurrance relation for Hermite polynomials: |
| template <class T1, class T2, class T3> |
| inline typename tools::promote_args<T1, T2, T3>::type |
| hermite_next(unsigned n, T1 x, T2 Hn, T3 Hnm1) |
| { |
| return (2 * x * Hn - 2 * n * Hnm1); |
| } |
| |
| namespace detail{ |
| |
| // Implement Hermite polynomials via recurrance: |
| template <class T> |
| T hermite_imp(unsigned n, T x) |
| { |
| T p0 = 1; |
| T p1 = 2 * x; |
| |
| if(n == 0) |
| return p0; |
| |
| unsigned c = 1; |
| |
| while(c < n) |
| { |
| std::swap(p0, p1); |
| p1 = hermite_next(c, x, p0, p1); |
| ++c; |
| } |
| return p1; |
| } |
| |
| } // namespace detail |
| |
| template <class T, class Policy> |
| inline typename tools::promote_args<T>::type |
| hermite(unsigned n, T x, const Policy&) |
| { |
| typedef typename tools::promote_args<T>::type result_type; |
| typedef typename policies::evaluation<result_type, Policy>::type value_type; |
| return policies::checked_narrowing_cast<result_type, Policy>(detail::hermite_imp(n, static_cast<value_type>(x)), "boost::math::hermite<%1%>(unsigned, %1%)"); |
| } |
| |
| template <class T> |
| inline typename tools::promote_args<T>::type |
| hermite(unsigned n, T x) |
| { |
| return boost::math::hermite(n, x, policies::policy<>()); |
| } |
| |
| } // namespace math |
| } // namespace boost |
| |
| #endif // BOOST_MATH_SPECIAL_HERMITE_HPP |
| |
| |
| |