1 // (C) Copyright John Maddock 2018.
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 #include <pch_light.hpp>
7 #include "test_sinc.hpp"
8 #include <boost/multiprecision/cpp_bin_float.hpp>
9 #include <boost/math/special_functions/next.hpp>
10
11 //
12 // DESCRIPTION:
13 // ~~~~~~~~~~~~
14 //
15 // This file tests the sinc_pi function. There are two sets of tests, spot
16 // tests which compare our results with selected values computed
17 // using the online special function calculator at
18 // functions.wolfram.com, while the bulk of the accuracy tests
19 // use values generated with NTL::RR at 1000-bit precision
20 // and our generic versions of these functions.
21 //
22 // Note that when this file is first run on a new platform many of
23 // these tests will fail: the default accuracy is 1 epsilon which
24 // is too tight for most platforms. In this situation you will
25 // need to cast a human eye over the error rates reported and make
26 // a judgement as to whether they are acceptable. Either way please
27 // report the results to the Boost mailing list. Acceptable rates of
28 // error are marked up below as a series of regular expressions that
29 // identify the compiler/stdlib/platform/data-type/test-data/test-function
30 // along with the maximum expected peek and RMS mean errors for that
31 // test.
32 //
33
expected_results()34 void expected_results()
35 {
36 //
37 // Define the max and mean errors expected for
38 // various compilers and platforms.
39 //
40 add_expected_result(
41 ".*", // compiler
42 ".*", // stdlib
43 ".*", // platform
44 ".*", // test type(s)
45 ".*", // test data group
46 ".*", 3, 3); // test function
47 //
48 // Finish off by printing out the compiler/stdlib/platform names,
49 // we do this to make it easier to mark up expected error rates.
50 //
51 std::cout << "Tests run with " << BOOST_COMPILER << ", "
52 << BOOST_STDLIB << ", " << BOOST_PLATFORM << std::endl;
53 }
54
55 template <class T>
test_close_to_transition()56 void test_close_to_transition()
57 {
58 T transition = 3.3f * boost::math::tools::forth_root_epsilon<T>();
59 T val = transition;
60
61 for (unsigned i = 0; i < 100; ++i)
62 {
63 boost::multiprecision::cpp_bin_float_50 extended = val;
64 extended = sin(extended) / extended;
65 T expected = extended.template convert_to<T>();
66 T result = boost::math::sinc_pi(val);
67 BOOST_CHECK_LE(boost::math::epsilon_difference(result, expected), 3);
68 result = boost::math::sinc_pi(-val);
69 BOOST_CHECK_LE(boost::math::epsilon_difference(result, expected), 3);
70 val = boost::math::float_prior(val);
71 }
72 for (unsigned i = 0; i < 100; ++i)
73 {
74 boost::multiprecision::cpp_bin_float_50 extended = val;
75 extended = sin(extended) / extended;
76 T expected = extended.template convert_to<T>();
77 T result = boost::math::sinc_pi(val);
78 BOOST_CHECK_LE(boost::math::epsilon_difference(result, expected), 3);
79 result = boost::math::sinc_pi(-val);
80 BOOST_CHECK_LE(boost::math::epsilon_difference(result, expected), 3);
81 val = boost::math::float_next(val);
82 }
83 }
84
85
BOOST_AUTO_TEST_CASE(test_main)86 BOOST_AUTO_TEST_CASE( test_main )
87 {
88 BOOST_MATH_CONTROL_FP;
89
90 expected_results();
91
92 test_sinc(0.1F, "float");
93 test_close_to_transition<float>();
94 test_sinc(0.1, "double");
95 test_close_to_transition<double>();
96 #ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
97 test_sinc(0.1L, "long double");
98 test_close_to_transition<long double>();
99 #ifndef BOOST_MATH_NO_REAL_CONCEPT_TESTS
100 test_sinc(boost::math::concepts::real_concept(0.1), "real_concept");
101 #endif
102 #else
103 std::cout << "<note>The long double tests have been disabled on this platform "
104 "either because the long double overloads of the usual math functions are "
105 "not available at all, or because they are too inaccurate for these tests "
106 "to pass.</note>" << std::endl;
107 #endif
108 }
109
110
111