1 | // Copyright John Maddock 2007. |
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_TRUNC_HPP |
7 | #define BOOST_MATH_TRUNC_HPP |
8 | |
9 | #ifdef _MSC_VER |
10 | #pragma once |
11 | #endif |
12 | |
13 | #include <boost/math/special_functions/math_fwd.hpp> |
14 | #include <boost/math/tools/config.hpp> |
15 | #include <boost/math/policies/error_handling.hpp> |
16 | #include <boost/math/special_functions/fpclassify.hpp> |
17 | #include <boost/type_traits/is_constructible.hpp> |
18 | #include <boost/core/enable_if.hpp> |
19 | |
20 | namespace boost{ namespace math{ namespace detail{ |
21 | |
22 | template <class T, class Policy> |
23 | inline typename tools::promote_args<T>::type trunc(const T& v, const Policy& pol, const boost::false_type&) |
24 | { |
25 | BOOST_MATH_STD_USING |
26 | typedef typename tools::promote_args<T>::type result_type; |
27 | if(!(boost::math::isfinite)(v)) |
28 | return policies::raise_rounding_error("boost::math::trunc<%1%>(%1%)" , 0, static_cast<result_type>(v), static_cast<result_type>(v), pol); |
29 | return (v >= 0) ? static_cast<result_type>(floor(v)) : static_cast<result_type>(ceil(v)); |
30 | } |
31 | |
32 | template <class T, class Policy> |
33 | inline typename tools::promote_args<T>::type trunc(const T& v, const Policy&, const boost::true_type&) |
34 | { |
35 | return v; |
36 | } |
37 | |
38 | } |
39 | |
40 | template <class T, class Policy> |
41 | inline typename tools::promote_args<T>::type trunc(const T& v, const Policy& pol) |
42 | { |
43 | return detail::trunc(v, pol, boost::integral_constant<bool, detail::is_integer_for_rounding<T>::value>()); |
44 | } |
45 | template <class T> |
46 | inline typename tools::promote_args<T>::type trunc(const T& v) |
47 | { |
48 | return trunc(v, policies::policy<>()); |
49 | } |
50 | // |
51 | // The following functions will not compile unless T has an |
52 | // implicit conversion to the integer types. For user-defined |
53 | // number types this will likely not be the case. In that case |
54 | // these functions should either be specialized for the UDT in |
55 | // question, or else overloads should be placed in the same |
56 | // namespace as the UDT: these will then be found via argument |
57 | // dependent lookup. See our concept archetypes for examples. |
58 | // |
59 | template <class T, class Policy> |
60 | inline int itrunc(const T& v, const Policy& pol) |
61 | { |
62 | BOOST_MATH_STD_USING |
63 | typedef typename tools::promote_args<T>::type result_type; |
64 | result_type r = boost::math::trunc(v, pol); |
65 | if((r > (std::numeric_limits<int>::max)()) || (r < (std::numeric_limits<int>::min)())) |
66 | return static_cast<int>(policies::raise_rounding_error("boost::math::itrunc<%1%>(%1%)" , 0, static_cast<result_type>(v), 0, pol)); |
67 | return static_cast<int>(r); |
68 | } |
69 | template <class T> |
70 | inline int itrunc(const T& v) |
71 | { |
72 | return itrunc(v, policies::policy<>()); |
73 | } |
74 | |
75 | template <class T, class Policy> |
76 | inline long ltrunc(const T& v, const Policy& pol) |
77 | { |
78 | BOOST_MATH_STD_USING |
79 | typedef typename tools::promote_args<T>::type result_type; |
80 | result_type r = boost::math::trunc(v, pol); |
81 | if((r > (std::numeric_limits<long>::max)()) || (r < (std::numeric_limits<long>::min)())) |
82 | return static_cast<long>(policies::raise_rounding_error("boost::math::ltrunc<%1%>(%1%)" , 0, static_cast<result_type>(v), 0L, pol)); |
83 | return static_cast<long>(r); |
84 | } |
85 | template <class T> |
86 | inline long ltrunc(const T& v) |
87 | { |
88 | return ltrunc(v, policies::policy<>()); |
89 | } |
90 | |
91 | #ifdef BOOST_HAS_LONG_LONG |
92 | |
93 | template <class T, class Policy> |
94 | inline boost::long_long_type lltrunc(const T& v, const Policy& pol) |
95 | { |
96 | BOOST_MATH_STD_USING |
97 | typedef typename tools::promote_args<T>::type result_type; |
98 | result_type r = boost::math::trunc(v, pol); |
99 | if((r > (std::numeric_limits<boost::long_long_type>::max)()) || (r < (std::numeric_limits<boost::long_long_type>::min)())) |
100 | return static_cast<boost::long_long_type>(policies::raise_rounding_error("boost::math::lltrunc<%1%>(%1%)" , 0, v, static_cast<boost::long_long_type>(0), pol)); |
101 | return static_cast<boost::long_long_type>(r); |
102 | } |
103 | template <class T> |
104 | inline boost::long_long_type lltrunc(const T& v) |
105 | { |
106 | return lltrunc(v, policies::policy<>()); |
107 | } |
108 | |
109 | #endif |
110 | |
111 | template <class T, class Policy> |
112 | inline typename boost::enable_if_c<boost::is_constructible<int, T>::value, int>::type |
113 | iconvert(const T& v, const Policy&) |
114 | { |
115 | return static_cast<int>(v); |
116 | } |
117 | |
118 | template <class T, class Policy> |
119 | inline typename boost::disable_if_c<boost::is_constructible<int, T>::value, int>::type |
120 | iconvert(const T& v, const Policy& pol) |
121 | { |
122 | using boost::math::itrunc; |
123 | return itrunc(v, pol); |
124 | } |
125 | |
126 | template <class T, class Policy> |
127 | inline typename boost::enable_if_c<boost::is_constructible<long, T>::value, long>::type |
128 | lconvert(const T& v, const Policy&) |
129 | { |
130 | return static_cast<long>(v); |
131 | } |
132 | |
133 | template <class T, class Policy> |
134 | inline typename boost::disable_if_c<boost::is_constructible<long, T>::value, long>::type |
135 | lconvert(const T& v, const Policy& pol) |
136 | { |
137 | using boost::math::ltrunc; |
138 | return ltrunc(v, pol); |
139 | } |
140 | |
141 | #ifdef BOOST_HAS_LONG_LONG |
142 | |
143 | template <class T, class Policy> |
144 | inline typename boost::enable_if_c<boost::is_constructible<boost::long_long_type, T>::value, boost::long_long_type>::type |
145 | llconvertert(const T& v, const Policy&) |
146 | { |
147 | return static_cast<boost::long_long_type>(v); |
148 | } |
149 | |
150 | template <class T, class Policy> |
151 | inline typename boost::disable_if_c<boost::is_constructible<boost::long_long_type, T>::value, boost::long_long_type>::type |
152 | llconvertert(const T& v, const Policy& pol) |
153 | { |
154 | using boost::math::lltrunc; |
155 | return lltrunc(v, pol); |
156 | } |
157 | |
158 | #endif |
159 | |
160 | }} // namespaces |
161 | |
162 | #endif // BOOST_MATH_TRUNC_HPP |
163 | |