annotate DEPENDENCIES/generic/include/boost/math/special_functions/hermite.hpp @ 133:4acb5d8d80b6 tip

Don't fail environmental check if README.md exists (but .txt and no-suffix don't)
author Chris Cannam
date Tue, 30 Jul 2019 12:25:44 +0100
parents 2665513ce2d3
children
rev   line source
Chris@16 1
Chris@16 2 // (C) Copyright John Maddock 2006.
Chris@16 3 // Use, modification and distribution are subject to the
Chris@16 4 // Boost Software License, Version 1.0. (See accompanying file
Chris@16 5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16 6
Chris@16 7 #ifndef BOOST_MATH_SPECIAL_HERMITE_HPP
Chris@16 8 #define BOOST_MATH_SPECIAL_HERMITE_HPP
Chris@16 9
Chris@16 10 #ifdef _MSC_VER
Chris@16 11 #pragma once
Chris@16 12 #endif
Chris@16 13
Chris@16 14 #include <boost/math/special_functions/math_fwd.hpp>
Chris@16 15 #include <boost/math/tools/config.hpp>
Chris@16 16 #include <boost/math/policies/error_handling.hpp>
Chris@16 17
Chris@16 18 namespace boost{
Chris@16 19 namespace math{
Chris@16 20
Chris@16 21 // Recurrance relation for Hermite polynomials:
Chris@16 22 template <class T1, class T2, class T3>
Chris@16 23 inline typename tools::promote_args<T1, T2, T3>::type
Chris@16 24 hermite_next(unsigned n, T1 x, T2 Hn, T3 Hnm1)
Chris@16 25 {
Chris@16 26 return (2 * x * Hn - 2 * n * Hnm1);
Chris@16 27 }
Chris@16 28
Chris@16 29 namespace detail{
Chris@16 30
Chris@16 31 // Implement Hermite polynomials via recurrance:
Chris@16 32 template <class T>
Chris@16 33 T hermite_imp(unsigned n, T x)
Chris@16 34 {
Chris@16 35 T p0 = 1;
Chris@16 36 T p1 = 2 * x;
Chris@16 37
Chris@16 38 if(n == 0)
Chris@16 39 return p0;
Chris@16 40
Chris@16 41 unsigned c = 1;
Chris@16 42
Chris@16 43 while(c < n)
Chris@16 44 {
Chris@16 45 std::swap(p0, p1);
Chris@16 46 p1 = hermite_next(c, x, p0, p1);
Chris@16 47 ++c;
Chris@16 48 }
Chris@16 49 return p1;
Chris@16 50 }
Chris@16 51
Chris@16 52 } // namespace detail
Chris@16 53
Chris@16 54 template <class T, class Policy>
Chris@16 55 inline typename tools::promote_args<T>::type
Chris@16 56 hermite(unsigned n, T x, const Policy&)
Chris@16 57 {
Chris@16 58 typedef typename tools::promote_args<T>::type result_type;
Chris@16 59 typedef typename policies::evaluation<result_type, Policy>::type value_type;
Chris@16 60 return policies::checked_narrowing_cast<result_type, Policy>(detail::hermite_imp(n, static_cast<value_type>(x)), "boost::math::hermite<%1%>(unsigned, %1%)");
Chris@16 61 }
Chris@16 62
Chris@16 63 template <class T>
Chris@16 64 inline typename tools::promote_args<T>::type
Chris@16 65 hermite(unsigned n, T x)
Chris@16 66 {
Chris@16 67 return boost::math::hermite(n, x, policies::policy<>());
Chris@16 68 }
Chris@16 69
Chris@16 70 } // namespace math
Chris@16 71 } // namespace boost
Chris@16 72
Chris@16 73 #endif // BOOST_MATH_SPECIAL_HERMITE_HPP
Chris@16 74
Chris@16 75
Chris@16 76