ceph/src/boost/libs/math/test/test_binomial_coeff.cpp

   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
  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>
  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
 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 #ifndef BOOST_MATH_NO_REAL_CONCEPT_TESTS
 124    test_spots(boost::math::concepts::real_concept(), "real_concept");
 125 #endif
 126 #endif
 127
 128    test_binomial(1.0F, "float");
 129    test_binomial(1.0, "double");
 130 #ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
 131    test_binomial(1.0L, "long double");
 132 #ifndef BOOST_MATH_NO_REAL_CONCEPT_TESTS
 133    test_binomial(boost::math::concepts::real_concept(), "real_concept");
 134 #endif
 135 #else
 136    std::cout << "<note>The long double tests have been disabled on this platform "
 137       "either because the long double overloads of the usual math functions are "
 138       "not available at all, or because they are too inaccurate for these tests "
 139       "to pass.</note>" << std::endl;
 140 #endif
 141 }
 142
 143
 144