1// Boost.Units - A C++ library for zero-overhead dimensional analysis and
2// unit/quantity manipulation and conversion
3//
4// Copyright (C) 2003-2008 Matthias Christian Schabel
5// Copyright (C) 2008 Steven Watanabe
6//
7// Distributed under the Boost Software License, Version 1.0. (See
8// accompanying file LICENSE_1_0.txt or copy at
9// http://www.boost.org/LICENSE_1_0.txt)
10
11/**
12\file
13
14\brief test_conversion.cpp
15
16\details
17Test conversion between quantities.
18
19Output:
20@verbatim
21@endverbatim
22**/
23
24#include <boost/units/quantity.hpp>
25#include <boost/units/systems/si.hpp>
26#include <boost/units/systems/cgs.hpp>
27
28#include <iostream>
29
30#include "test_close.hpp"
31
32#define BOOST_UNITS_CHECK_CLOSE(a, b) BOOST_UNITS_TEST_CLOSE((a), (b), .0000001)
33
34namespace bu = boost::units;
35
36typedef bu::si::length si_length;
37typedef bu::si::time si_time;
38typedef bu::si::mass si_mass;
39typedef bu::si::area si_area;
40
41typedef bu::cgs::length cgs_length;
42typedef bu::cgs::time cgs_time;
43typedef bu::cgs::mass cgs_mass;
44typedef bu::cgs::area cgs_area;
45
46typedef bu::multiply_typeof_helper<si_length, cgs_length>::type mixed_length;
47typedef bu::multiply_typeof_helper<si_time, cgs_time>::type mixed_time;
48
49typedef bu::divide_typeof_helper<bu::multiply_typeof_helper<si_mass,cgs_area>::type, mixed_time>::type mixed_energy_1;
50typedef bu::divide_typeof_helper<bu::multiply_typeof_helper<cgs_mass,mixed_length>::type,
51 bu::multiply_typeof_helper<cgs_time,cgs_time>::type >::type mixed_energy_2;
52
53void test_conversion() {
54 BOOST_TEST_EQ(1, 1);
55 BOOST_CONSTEXPR_OR_CONST bu::quantity<mixed_length> a1(2.0 * mixed_length());
56 BOOST_CONSTEXPR_OR_CONST bu::quantity<si_area> a2(a1);
57
58 BOOST_UNITS_CHECK_CLOSE(a2.value(), .02);
59
60 BOOST_CONSTEXPR_OR_CONST bu::quantity<mixed_length> a3(a2);
61
62 BOOST_UNITS_CHECK_CLOSE(a3.value(), 2.0);
63
64 BOOST_CONSTEXPR_OR_CONST bu::quantity<mixed_energy_1> e1(2.0 * mixed_energy_1());
65 BOOST_CONSTEXPR_OR_CONST bu::quantity<mixed_energy_2> e2(e1);
66
67 BOOST_UNITS_CHECK_CLOSE(e2.value(), 20.0);
68
69 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::si::energy> e3(e1);
70 BOOST_UNITS_CHECK_CLOSE(e3.value(), .0002);
71 BOOST_CONSTEXPR_OR_CONST bu::quantity<mixed_energy_2> e4(e3);
72 BOOST_UNITS_CHECK_CLOSE(e4.value(), 20.0);
73
74 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::cgs::force> F0 = 20 * bu::cgs::dyne;
75 BOOST_UNITS_CHECK_CLOSE(F0.value(), 20.0);
76
77 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::si::force> F3(F0);
78 BOOST_UNITS_CHECK_CLOSE(F3.value(), 2.0e-4);
79
80 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::si::force> F5(20 * bu::cgs::dyne);
81 BOOST_UNITS_CHECK_CLOSE(F5.value(), 2.0e-4);
82
83 // same type
84 BOOST_TEST_EQ(boost::units::conversion_factor(si_length(), si_length()), 1.0);
85}
86
87void test_dimensionless_conversions() {
88 typedef bu::divide_typeof_helper<bu::cgs::force, bu::si::force>::type mixed_dimensionless;
89
90 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::si::dimensionless> dimensionless_test1(1.0*bu::cgs::dyne/bu::si::newton);
91 BOOST_TEST(dimensionless_test1 == 1e-5);
92
93 typedef bu::multiply_typeof_helper<bu::si::length, bu::cgs::length>::type m_cm;
94 typedef bu::divide_typeof_helper<m_cm, m_cm>::type heterogeneous_dimensionless;
95 BOOST_CONSTEXPR_OR_CONST bu::quantity<heterogeneous_dimensionless> dimensionless_test2(1.0*bu::cgs::dyne/bu::si::newton);
96 BOOST_TEST(dimensionless_test2.value() == 1e-5);
97 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::divide_typeof_helper<bu::cgs::force, bu::si::force>::type> dimensionless_test3(dimensionless_test2);
98 BOOST_UNITS_CHECK_CLOSE(dimensionless_test3.value(), 1.0);
99
100 BOOST_UNITS_CHECK_CLOSE(boost::units::conversion_factor(mixed_dimensionless(), heterogeneous_dimensionless()), 1e-5);
101 BOOST_UNITS_CHECK_CLOSE(boost::units::conversion_factor(heterogeneous_dimensionless(), mixed_dimensionless()), 1e5);
102
103
104 //m/cm -> g/kg
105 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::divide_typeof_helper<bu::si::length, bu::cgs::length>::type> dimensionless_test4(2.0 * bu::si::meters / bu::cgs::centimeters);
106 BOOST_CONSTEXPR_OR_CONST bu::quantity<bu::divide_typeof_helper<bu::cgs::mass, bu::si::mass>::type> dimensionless_test5(dimensionless_test4);
107 BOOST_UNITS_CHECK_CLOSE(dimensionless_test5.value(), 2e5);
108}
109
110int main()
111{
112 test_conversion();
113 test_dimensionless_conversions();
114 return boost::report_errors();
115}
116

source code of boost/libs/units/test/test_conversion.cpp