1 // (C) Copyright John Maddock 2006.
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.hpp>
7 #include "test_binomial_coeff.hpp"
8
9 //
10 // DESCRIPTION:
11 // ~~~~~~~~~~~~
12 //
13 // This file tests the function binomial_coefficient<T>.
14 // The accuracy tests
15 // use values generated with NTL::RR at 1000-bit precision
16 // and our generic versions of these function.
17 //
18 // Note that when this file is first run on a new platform many of
19 // these tests will fail: the default accuracy is 1 epsilon which
20 // is too tight for most platforms. In this situation you will
21 // need to cast a human eye over the error rates reported and make
22 // a judgement as to whether they are acceptable. Either way please
23 // report the results to the Boost mailing list. Acceptable rates of
24 // error are marked up below as a series of regular expressions that
25 // identify the compiler/stdlib/platform/data-type/test-data/test-function
26 // along with the maximum expected peek and RMS mean errors for that
27 // test.
28 //
29
expected_results()30 void expected_results()
31 {
32 //
33 // Define the max and mean errors expected for
34 // various compilers and platforms.
35 //
36 const char* largest_type;
37 #ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
38 if(boost::math::policies::digits<double, boost::math::policies::policy<> >() == boost::math::policies::digits<long double, boost::math::policies::policy<> >())
39 {
40 largest_type = "(long\\s+)?double";
41 }
42 else
43 {
44 largest_type = "long double";
45 }
46 #else
47 largest_type = "(long\\s+)?double";
48 #endif
49 add_expected_result(
50 ".*", // compiler
51 ".*", // stdlib
52 ".*", // platform
53 largest_type, // test type(s)
54 ".*large.*", // test data group
55 ".*", 100, 20); // test function
56 add_expected_result(
57 ".*", // compiler
58 ".*", // stdlib
59 ".*", // platform
60 "real_concept", // test type(s)
61 ".*large.*", // test data group
62 ".*", 250, 100); // test function
63 add_expected_result(
64 ".*", // compiler
65 ".*", // stdlib
66 ".*", // platform
67 "real_concept", // test type(s)
68 ".*", // test data group
69 ".*", 150, 30); // test function
70 add_expected_result(
71 ".*", // compiler
72 ".*", // stdlib
73 ".*", // platform
74 ".*", // test type(s)
75 ".*", // test data group
76 ".*", 2, 1); // test function
77
78 //
79 // Finish off by printing out the compiler/stdlib/platform names,
80 // we do this to make it easier to mark up expected error rates.
81 //
82 std::cout << "Tests run with " << BOOST_COMPILER << ", "
83 << BOOST_STDLIB << ", " << BOOST_PLATFORM << std::endl;
84 }
85
86 template <class T>
test_spots(T,const char * name)87 void test_spots(T, const char* name)
88 {
89 T tolerance = boost::math::tools::epsilon<T>() * 50 * 100; // 50 eps as a percentage
90 if(!std::numeric_limits<T>::is_specialized)
91 tolerance *= 10; // beta function not so accurate without lanczos support
92
93 std::cout << "Testing spot checks for type " << name << " with tolerance " << tolerance << "%\n";
94
95 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 0), static_cast<T>(1));
96 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 1), static_cast<T>(20));
97 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 2), static_cast<T>(190));
98 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 3), static_cast<T>(1140));
99 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 20), static_cast<T>(1));
100 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 19), static_cast<T>(20));
101 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 18), static_cast<T>(190));
102 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 17), static_cast<T>(1140));
103 BOOST_CHECK_EQUAL(boost::math::binomial_coefficient<T>(20, 10), static_cast<T>(184756L));
104
105 BOOST_CHECK_CLOSE(boost::math::binomial_coefficient<T>(100, 5), static_cast<T>(7.528752e7L), tolerance);
106 BOOST_CHECK_CLOSE(boost::math::binomial_coefficient<T>(100, 81), static_cast<T>(1.323415729392122674e20L), tolerance);
107
108 BOOST_CHECK_CLOSE(boost::math::binomial_coefficient<T>(300, 3), static_cast<T>(4.45510e6L), tolerance);
109 BOOST_CHECK_CLOSE(boost::math::binomial_coefficient<T>(300, 7), static_cast<T>(4.043855956140000e13L), tolerance);
110 BOOST_CHECK_CLOSE(boost::math::binomial_coefficient<T>(300, 290), static_cast<T>(1.3983202332417017700000000e18L), tolerance);
111 BOOST_CHECK_CLOSE(boost::math::binomial_coefficient<T>(300, 275), static_cast<T>(1.953265141442868389822364184842211512000000e36L), tolerance);
112 }
113
BOOST_AUTO_TEST_CASE(test_main)114 BOOST_AUTO_TEST_CASE( test_main )
115 {
116 expected_results();
117 BOOST_MATH_CONTROL_FP;
118
119 test_spots(1.0F, "float");
120 test_spots(1.0, "double");
121 #ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
122 test_spots(1.0L, "long double");
123 test_spots(boost::math::concepts::real_concept(), "real_concept");
124 #endif
125
126 test_binomial(1.0F, "float");
127 test_binomial(1.0, "double");
128 #ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
129 test_binomial(1.0L, "long double");
130 #ifndef BOOST_MATH_NO_REAL_CONCEPT_TESTS
131 test_binomial(boost::math::concepts::real_concept(), "real_concept");
132 #endif
133 #else
134 std::cout << "<note>The long double tests have been disabled on this platform "
135 "either because the long double overloads of the usual math functions are "
136 "not available at all, or because they are too inaccurate for these tests "
137 "to pass.</note>" << std::endl;
138 #endif
139 }
140
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143