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
18 namespace boost{ namespace math{ namespace detail{
19
20 template <class T, class Policy>
trunc(const T & v,const Policy & pol,const mpl::false_ &)21 inline typename tools::promote_args<T>::type trunc(const T& v, const Policy& pol, const mpl::false_&)
22 {
23 BOOST_MATH_STD_USING
24 typedef typename tools::promote_args<T>::type result_type;
25 if(!(boost::math::isfinite)(v))
26 return policies::raise_rounding_error("boost::math::trunc<%1%>(%1%)", 0, static_cast<result_type>(v), static_cast<result_type>(v), pol);
27 return (v >= 0) ? static_cast<result_type>(floor(v)) : static_cast<result_type>(ceil(v));
28 }
29
30 template <class T, class Policy>
trunc(const T & v,const Policy &,const mpl::true_ &)31 inline typename tools::promote_args<T>::type trunc(const T& v, const Policy&, const mpl::true_&)
32 {
33 return v;
34 }
35
36 }
37
38 template <class T, class Policy>
trunc(const T & v,const Policy & pol)39 inline typename tools::promote_args<T>::type trunc(const T& v, const Policy& pol)
40 {
41 return detail::trunc(v, pol, mpl::bool_<detail::is_integer_for_rounding<T>::value>());
42 }
43 template <class T>
trunc(const T & v)44 inline typename tools::promote_args<T>::type trunc(const T& v)
45 {
46 return trunc(v, policies::policy<>());
47 }
48 //
49 // The following functions will not compile unless T has an
50 // implicit convertion to the integer types. For user-defined
51 // number types this will likely not be the case. In that case
52 // these functions should either be specialized for the UDT in
53 // question, or else overloads should be placed in the same
54 // namespace as the UDT: these will then be found via argument
55 // dependent lookup. See our concept archetypes for examples.
56 //
57 template <class T, class Policy>
itrunc(const T & v,const Policy & pol)58 inline int itrunc(const T& v, const Policy& pol)
59 {
60 BOOST_MATH_STD_USING
61 typedef typename tools::promote_args<T>::type result_type;
62 result_type r = boost::math::trunc(v, pol);
63 if((r > (std::numeric_limits<int>::max)()) || (r < (std::numeric_limits<int>::min)()))
64 return static_cast<int>(policies::raise_rounding_error("boost::math::itrunc<%1%>(%1%)", 0, static_cast<result_type>(v), 0, pol));
65 return static_cast<int>(r);
66 }
67 template <class T>
itrunc(const T & v)68 inline int itrunc(const T& v)
69 {
70 return itrunc(v, policies::policy<>());
71 }
72
73 template <class T, class Policy>
ltrunc(const T & v,const Policy & pol)74 inline long ltrunc(const T& v, const Policy& pol)
75 {
76 BOOST_MATH_STD_USING
77 typedef typename tools::promote_args<T>::type result_type;
78 result_type r = boost::math::trunc(v, pol);
79 if((r > (std::numeric_limits<long>::max)()) || (r < (std::numeric_limits<long>::min)()))
80 return static_cast<long>(policies::raise_rounding_error("boost::math::ltrunc<%1%>(%1%)", 0, static_cast<result_type>(v), 0L, pol));
81 return static_cast<long>(r);
82 }
83 template <class T>
ltrunc(const T & v)84 inline long ltrunc(const T& v)
85 {
86 return ltrunc(v, policies::policy<>());
87 }
88
89 #ifdef BOOST_HAS_LONG_LONG
90
91 template <class T, class Policy>
lltrunc(const T & v,const Policy & pol)92 inline boost::long_long_type lltrunc(const T& v, const Policy& pol)
93 {
94 BOOST_MATH_STD_USING
95 typedef typename tools::promote_args<T>::type result_type;
96 result_type r = boost::math::trunc(v, pol);
97 if((r > (std::numeric_limits<boost::long_long_type>::max)()) || (r < (std::numeric_limits<boost::long_long_type>::min)()))
98 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));
99 return static_cast<boost::long_long_type>(r);
100 }
101 template <class T>
lltrunc(const T & v)102 inline boost::long_long_type lltrunc(const T& v)
103 {
104 return lltrunc(v, policies::policy<>());
105 }
106
107 #endif
108
109 }} // namespaces
110
111 #endif // BOOST_MATH_TRUNC_HPP
112