diff options
Diffstat (limited to 'libcxx')
| -rw-r--r-- | libcxx/include/random | 5 | ||||
| -rw-r--r-- | libcxx/test/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp | 11 |
2 files changed, 15 insertions, 1 deletions
diff --git a/libcxx/include/random b/libcxx/include/random index c0db1abacc0..e7053ce4ecf 100644 --- a/libcxx/include/random +++ b/libcxx/include/random @@ -4009,6 +4009,8 @@ binomial_distribution<_IntType>::param_type::param_type(result_type __t, double } } +// Reference: Kemp, C.D. (1986). `A modal method for generating binomial +// variables', Commun. Statist. - Theor. Meth. 15(3), 805-813. template<class _IntType> template<class _URNG> _IntType @@ -4035,7 +4037,8 @@ binomial_distribution<_IntType>::operator()(_URNG& __g, const param_type& __pr) if (__u < 0) return __rd - 1; } - --__rd; + if ( __rd != 0 ) + --__rd; ++__ru; if (__ru <= __pr.__t_) { diff --git a/libcxx/test/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp b/libcxx/test/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp index 3bfd2af6106..85ff2ac4750 100644 --- a/libcxx/test/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp +++ b/libcxx/test/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp @@ -322,6 +322,17 @@ int main() assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01); } { + const int N = 100000; + std::mt19937 gen1; + std::mt19937 gen2; + + std::binomial_distribution<> dist1(5, 0.1); + std::binomial_distribution<unsigned> dist2(5, 0.1); + + for(int i = 0; i < N; ++i) + assert(dist1(gen1) == dist2(gen2)); + } + { typedef std::binomial_distribution<> D; typedef std::mt19937 G; G g; |
