297 lines
		
	
	
		
			8.2 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			297 lines
		
	
	
		
			8.2 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===----------------------------------------------------------------------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is dual licensed under the MIT and the University of Illinois Open
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| // Source Licenses. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // REQUIRES: long_tests
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| 
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| // <random>
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| 
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| // template<class IntType = int>
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| // class negative_binomial_distribution
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| 
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| // template<class _URNG> result_type operator()(_URNG& g);
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| 
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| #include <random>
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| #include <numeric>
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| #include <vector>
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| #include <cassert>
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| 
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| template <class T>
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| inline
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| T
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| sqr(T x)
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| {
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|     return x * x;
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| }
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| 
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| void
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| test1()
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| {
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|     typedef std::negative_binomial_distribution<> D;
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|     typedef std::minstd_rand G;
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|     G g;
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|     D d(5, .25);
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|     const int N = 1000000;
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|     std::vector<D::result_type> u;
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|     for (int i = 0; i < N; ++i)
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|     {
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|         D::result_type v = d(g);
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|         assert(d.min() <= v && v <= d.max());
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|         u.push_back(v);
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|     }
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|     double mean = std::accumulate(u.begin(), u.end(),
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|                                           double(0)) / u.size();
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|     double var = 0;
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|     double skew = 0;
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|     double kurtosis = 0;
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|     for (int i = 0; i < u.size(); ++i)
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|     {
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|         double dbl = (u[i] - mean);
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|         double d2 = sqr(dbl);
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|         var += d2;
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|         skew += dbl * d2;
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|         kurtosis += d2 * d2;
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|     }
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|     var /= u.size();
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|     double dev = std::sqrt(var);
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|     skew /= u.size() * dev * var;
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|     kurtosis /= u.size() * var * var;
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|     kurtosis -= 3;
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|     double x_mean = d.k() * (1 - d.p()) / d.p();
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|     double x_var = x_mean / d.p();
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|     double x_skew = (2 - d.p()) / std::sqrt(d.k() * (1 - d.p()));
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|     double x_kurtosis = 6. / d.k() + sqr(d.p()) / (d.k() * (1 - d.p()));
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|     assert(std::abs((mean - x_mean) / x_mean) < 0.01);
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|     assert(std::abs((var - x_var) / x_var) < 0.01);
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|     assert(std::abs((skew - x_skew) / x_skew) < 0.01);
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|     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.02);
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| }
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| 
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| void
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| test2()
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| {
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|     typedef std::negative_binomial_distribution<> D;
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|     typedef std::mt19937 G;
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|     G g;
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|     D d(30, .03125);
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|     const int N = 1000000;
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|     std::vector<D::result_type> u;
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|     for (int i = 0; i < N; ++i)
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|     {
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|         D::result_type v = d(g);
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|         assert(d.min() <= v && v <= d.max());
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|         u.push_back(v);
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|     }
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|     double mean = std::accumulate(u.begin(), u.end(),
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|                                           double(0)) / u.size();
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|     double var = 0;
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|     double skew = 0;
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|     double kurtosis = 0;
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|     for (int i = 0; i < u.size(); ++i)
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|     {
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|         double dbl = (u[i] - mean);
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|         double d2 = sqr(dbl);
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|         var += d2;
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|         skew += dbl * d2;
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|         kurtosis += d2 * d2;
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|     }
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|     var /= u.size();
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|     double dev = std::sqrt(var);
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|     skew /= u.size() * dev * var;
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|     kurtosis /= u.size() * var * var;
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|     kurtosis -= 3;
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|     double x_mean = d.k() * (1 - d.p()) / d.p();
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|     double x_var = x_mean / d.p();
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|     double x_skew = (2 - d.p()) / std::sqrt(d.k() * (1 - d.p()));
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|     double x_kurtosis = 6. / d.k() + sqr(d.p()) / (d.k() * (1 - d.p()));
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|     assert(std::abs((mean - x_mean) / x_mean) < 0.01);
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|     assert(std::abs((var - x_var) / x_var) < 0.01);
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|     assert(std::abs((skew - x_skew) / x_skew) < 0.01);
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|     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
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| }
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| 
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| void
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| test3()
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| {
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|     typedef std::negative_binomial_distribution<> D;
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|     typedef std::mt19937 G;
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|     G g;
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|     D d(40, .25);
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|     const int N = 1000000;
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|     std::vector<D::result_type> u;
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|     for (int i = 0; i < N; ++i)
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|     {
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|         D::result_type v = d(g);
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|         assert(d.min() <= v && v <= d.max());
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|         u.push_back(v);
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|     }
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|     double mean = std::accumulate(u.begin(), u.end(),
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|                                           double(0)) / u.size();
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|     double var = 0;
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|     double skew = 0;
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|     double kurtosis = 0;
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|     for (int i = 0; i < u.size(); ++i)
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|     {
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|         double dbl = (u[i] - mean);
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|         double d2 = sqr(dbl);
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|         var += d2;
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|         skew += dbl * d2;
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|         kurtosis += d2 * d2;
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|     }
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|     var /= u.size();
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|     double dev = std::sqrt(var);
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|     skew /= u.size() * dev * var;
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|     kurtosis /= u.size() * var * var;
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|     kurtosis -= 3;
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|     double x_mean = d.k() * (1 - d.p()) / d.p();
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|     double x_var = x_mean / d.p();
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|     double x_skew = (2 - d.p()) / std::sqrt(d.k() * (1 - d.p()));
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|     double x_kurtosis = 6. / d.k() + sqr(d.p()) / (d.k() * (1 - d.p()));
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|     assert(std::abs((mean - x_mean) / x_mean) < 0.01);
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|     assert(std::abs((var - x_var) / x_var) < 0.01);
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|     assert(std::abs((skew - x_skew) / x_skew) < 0.01);
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|     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.03);
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| }
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| 
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| void
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| test4()
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| {
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|     typedef std::negative_binomial_distribution<> D;
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|     typedef std::mt19937 G;
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|     G g;
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|     D d(40, 1);
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|     const int N = 1000;
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|     std::vector<D::result_type> u;
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|     for (int i = 0; i < N; ++i)
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|     {
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|         D::result_type v = d(g);
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|         assert(d.min() <= v && v <= d.max());
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|         u.push_back(v);
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|     }
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|     double mean = std::accumulate(u.begin(), u.end(),
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|                                           double(0)) / u.size();
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|     double var = 0;
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|     double skew = 0;
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|     double kurtosis = 0;
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|     for (int i = 0; i < u.size(); ++i)
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|     {
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|         double dbl = (u[i] - mean);
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|         double d2 = sqr(dbl);
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|         var += d2;
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|         skew += dbl * d2;
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|         kurtosis += d2 * d2;
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|     }
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|     var /= u.size();
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|     double dev = std::sqrt(var);
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|     skew /= u.size() * dev * var;
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|     kurtosis /= u.size() * var * var;
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|     kurtosis -= 3;
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|     double x_mean = d.k() * (1 - d.p()) / d.p();
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|     double x_var = x_mean / d.p();
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|     double x_skew = (2 - d.p()) / std::sqrt(d.k() * (1 - d.p()));
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|     double x_kurtosis = 6. / d.k() + sqr(d.p()) / (d.k() * (1 - d.p()));
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|     assert(mean == x_mean);
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|     assert(var == x_var);
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| }
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| 
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| void
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| test5()
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| {
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|     typedef std::negative_binomial_distribution<> D;
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|     typedef std::mt19937 G;
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|     G g;
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|     D d(400, 0.5);
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|     const int N = 1000000;
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|     std::vector<D::result_type> u;
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|     for (int i = 0; i < N; ++i)
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|     {
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|         D::result_type v = d(g);
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|         assert(d.min() <= v && v <= d.max());
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|         u.push_back(v);
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|     }
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|     double mean = std::accumulate(u.begin(), u.end(),
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|                                           double(0)) / u.size();
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|     double var = 0;
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|     double skew = 0;
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|     double kurtosis = 0;
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|     for (int i = 0; i < u.size(); ++i)
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|     {
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|         double dbl = (u[i] - mean);
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|         double d2 = sqr(dbl);
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|         var += d2;
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|         skew += dbl * d2;
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|         kurtosis += d2 * d2;
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|     }
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|     var /= u.size();
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|     double dev = std::sqrt(var);
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|     skew /= u.size() * dev * var;
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|     kurtosis /= u.size() * var * var;
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|     kurtosis -= 3;
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|     double x_mean = d.k() * (1 - d.p()) / d.p();
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|     double x_var = x_mean / d.p();
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|     double x_skew = (2 - d.p()) / std::sqrt(d.k() * (1 - d.p()));
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|     double x_kurtosis = 6. / d.k() + sqr(d.p()) / (d.k() * (1 - d.p()));
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|     assert(std::abs((mean - x_mean) / x_mean) < 0.01);
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|     assert(std::abs((var - x_var) / x_var) < 0.01);
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|     assert(std::abs((skew - x_skew) / x_skew) < 0.04);
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|     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.05);
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| }
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| 
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| void
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| test6()
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| {
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|     typedef std::negative_binomial_distribution<> D;
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|     typedef std::mt19937 G;
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|     G g;
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|     D d(1, 0.05);
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|     const int N = 1000000;
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|     std::vector<D::result_type> u;
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|     for (int i = 0; i < N; ++i)
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|     {
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|         D::result_type v = d(g);
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|         assert(d.min() <= v && v <= d.max());
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|         u.push_back(v);
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|     }
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|     double mean = std::accumulate(u.begin(), u.end(),
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|                                           double(0)) / u.size();
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|     double var = 0;
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|     double skew = 0;
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|     double kurtosis = 0;
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|     for (int i = 0; i < u.size(); ++i)
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|     {
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|         double dbl = (u[i] - mean);
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|         double d2 = sqr(dbl);
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|         var += d2;
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|         skew += dbl * d2;
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|         kurtosis += d2 * d2;
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|     }
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|     var /= u.size();
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|     double dev = std::sqrt(var);
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|     skew /= u.size() * dev * var;
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|     kurtosis /= u.size() * var * var;
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|     kurtosis -= 3;
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|     double x_mean = d.k() * (1 - d.p()) / d.p();
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|     double x_var = x_mean / d.p();
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|     double x_skew = (2 - d.p()) / std::sqrt(d.k() * (1 - d.p()));
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|     double x_kurtosis = 6. / d.k() + sqr(d.p()) / (d.k() * (1 - d.p()));
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|     assert(std::abs((mean - x_mean) / x_mean) < 0.01);
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|     assert(std::abs((var - x_var) / x_var) < 0.01);
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|     assert(std::abs((skew - x_skew) / x_skew) < 0.01);
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|     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.03);
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| }
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| 
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| int main()
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| {
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|     test1();
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|     test2();
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|     test3();
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|     test4();
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|     test5();
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|     test6();
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| }
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