diff any/include/boost/math/distributions/detail/hypergeometric_quantile.hpp @ 160:cff480c41f97

Add some cross-platform Boost headers
author Chris Cannam <cannam@all-day-breakfast.com>
date Sat, 16 Feb 2019 16:31:25 +0000
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/any/include/boost/math/distributions/detail/hypergeometric_quantile.hpp	Sat Feb 16 16:31:25 2019 +0000
@@ -0,0 +1,245 @@
+// Copyright 2008 John Maddock
+//
+// Use, modification and distribution are subject to the
+// Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_MATH_DISTRIBUTIONS_DETAIL_HG_QUANTILE_HPP
+#define BOOST_MATH_DISTRIBUTIONS_DETAIL_HG_QUANTILE_HPP
+
+#include <boost/math/policies/error_handling.hpp>
+#include <boost/math/distributions/detail/hypergeometric_pdf.hpp>
+
+namespace boost{ namespace math{ namespace detail{
+
+template <class T>
+inline unsigned round_x_from_p(unsigned x, T p, T cum, T fudge_factor, unsigned lbound, unsigned /*ubound*/, const policies::discrete_quantile<policies::integer_round_down>&)
+{
+   if((p < cum * fudge_factor) && (x != lbound))
+   {
+      BOOST_MATH_INSTRUMENT_VARIABLE(x-1);
+      return --x;
+   }
+   return x;
+}
+
+template <class T>
+inline unsigned round_x_from_p(unsigned x, T p, T cum, T fudge_factor, unsigned /*lbound*/, unsigned ubound, const policies::discrete_quantile<policies::integer_round_up>&)
+{
+   if((cum < p * fudge_factor) && (x != ubound))
+   {
+      BOOST_MATH_INSTRUMENT_VARIABLE(x+1);
+      return ++x;
+   }
+   return x;
+}
+
+template <class T>
+inline unsigned round_x_from_p(unsigned x, T p, T cum, T fudge_factor, unsigned lbound, unsigned ubound, const policies::discrete_quantile<policies::integer_round_inwards>&)
+{
+   if(p >= 0.5)
+      return round_x_from_p(x, p, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_down>());
+   return round_x_from_p(x, p, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_up>());
+}
+
+template <class T>
+inline unsigned round_x_from_p(unsigned x, T p, T cum, T fudge_factor, unsigned lbound, unsigned ubound, const policies::discrete_quantile<policies::integer_round_outwards>&)
+{
+   if(p >= 0.5)
+      return round_x_from_p(x, p, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_up>());
+   return round_x_from_p(x, p, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_down>());
+}
+
+template <class T>
+inline unsigned round_x_from_p(unsigned x, T /*p*/, T /*cum*/, T /*fudge_factor*/, unsigned /*lbound*/, unsigned /*ubound*/, const policies::discrete_quantile<policies::integer_round_nearest>&)
+{
+   return x;
+}
+
+template <class T>
+inline unsigned round_x_from_q(unsigned x, T q, T cum, T fudge_factor, unsigned lbound, unsigned /*ubound*/, const policies::discrete_quantile<policies::integer_round_down>&)
+{
+   if((q * fudge_factor > cum) && (x != lbound))
+   {
+      BOOST_MATH_INSTRUMENT_VARIABLE(x-1);
+      return --x;
+   }
+   return x;
+}
+
+template <class T>
+inline unsigned round_x_from_q(unsigned x, T q, T cum, T fudge_factor, unsigned /*lbound*/, unsigned ubound, const policies::discrete_quantile<policies::integer_round_up>&)
+{
+   if((q < cum * fudge_factor) && (x != ubound))
+   {
+      BOOST_MATH_INSTRUMENT_VARIABLE(x+1);
+      return ++x;
+   }
+   return x;
+}
+
+template <class T>
+inline unsigned round_x_from_q(unsigned x, T q, T cum, T fudge_factor, unsigned lbound, unsigned ubound, const policies::discrete_quantile<policies::integer_round_inwards>&)
+{
+   if(q < 0.5)
+      return round_x_from_q(x, q, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_down>());
+   return round_x_from_q(x, q, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_up>());
+}
+
+template <class T>
+inline unsigned round_x_from_q(unsigned x, T q, T cum, T fudge_factor, unsigned lbound, unsigned ubound, const policies::discrete_quantile<policies::integer_round_outwards>&)
+{
+   if(q >= 0.5)
+      return round_x_from_q(x, q, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_down>());
+   return round_x_from_q(x, q, cum, fudge_factor, lbound, ubound, policies::discrete_quantile<policies::integer_round_up>());
+}
+
+template <class T>
+inline unsigned round_x_from_q(unsigned x, T /*q*/, T /*cum*/, T /*fudge_factor*/, unsigned /*lbound*/, unsigned /*ubound*/, const policies::discrete_quantile<policies::integer_round_nearest>&)
+{
+   return x;
+}
+
+template <class T, class Policy>
+unsigned hypergeometric_quantile_imp(T p, T q, unsigned r, unsigned n, unsigned N, const Policy& pol)
+{
+#ifdef BOOST_MSVC
+#  pragma warning(push)
+#  pragma warning(disable:4267)
+#endif
+   typedef typename Policy::discrete_quantile_type discrete_quantile_type;
+   BOOST_MATH_STD_USING
+   BOOST_FPU_EXCEPTION_GUARD
+   T result;
+   T fudge_factor = 1 + tools::epsilon<T>() * ((N <= boost::math::prime(boost::math::max_prime - 1)) ? 50 : 2 * N);
+   unsigned base = static_cast<unsigned>((std::max)(0, (int)(n + r) - (int)(N)));
+   unsigned lim = (std::min)(r, n);
+
+   BOOST_MATH_INSTRUMENT_VARIABLE(p);
+   BOOST_MATH_INSTRUMENT_VARIABLE(q);
+   BOOST_MATH_INSTRUMENT_VARIABLE(r);
+   BOOST_MATH_INSTRUMENT_VARIABLE(n);
+   BOOST_MATH_INSTRUMENT_VARIABLE(N);
+   BOOST_MATH_INSTRUMENT_VARIABLE(fudge_factor);
+   BOOST_MATH_INSTRUMENT_VARIABLE(base);
+   BOOST_MATH_INSTRUMENT_VARIABLE(lim);
+
+   if(p <= 0.5)
+   {
+      unsigned x = base;
+      result = hypergeometric_pdf<T>(x, r, n, N, pol);
+      T diff = result;
+      if (diff == 0)
+      {
+         ++x;
+         // We want to skip through x values as fast as we can until we start getting non-zero values,
+         // otherwise we're just making lots of expensive PDF calls:
+         T log_pdf = boost::math::lgamma(static_cast<T>(n + 1), pol)
+            + boost::math::lgamma(static_cast<T>(r + 1), pol)
+            + boost::math::lgamma(static_cast<T>(N - n + 1), pol)
+            + boost::math::lgamma(static_cast<T>(N - r + 1), pol)
+            - boost::math::lgamma(static_cast<T>(N + 1), pol)
+            - boost::math::lgamma(static_cast<T>(x + 1), pol)
+            - boost::math::lgamma(static_cast<T>(n - x + 1), pol)
+            - boost::math::lgamma(static_cast<T>(r - x + 1), pol)
+            - boost::math::lgamma(static_cast<T>(N - n - r + x + 1), pol);
+         while (log_pdf < tools::log_min_value<T>())
+         {
+            log_pdf += -log(static_cast<T>(x + 1)) + log(static_cast<T>(n - x)) + log(static_cast<T>(r - x)) - log(static_cast<T>(N - n - r + x + 1));
+            ++x;
+         }
+         // By the time we get here, log_pdf may be fairly inaccurate due to
+         // roundoff errors, get a fresh PDF calculation before proceding:
+         diff = hypergeometric_pdf<T>(x, r, n, N, pol);
+      }
+      while(result < p)
+      {
+         diff = (diff > tools::min_value<T>() * 8) 
+            ? T(n - x) * T(r - x) * diff / (T(x + 1) * T(N + x + 1 - n - r))
+            : hypergeometric_pdf<T>(x + 1, r, n, N, pol);
+         if(result + diff / 2 > p)
+            break;
+         ++x;
+         result += diff;
+#ifdef BOOST_MATH_INSTRUMENT
+         if(diff != 0)
+         {
+            BOOST_MATH_INSTRUMENT_VARIABLE(x);
+            BOOST_MATH_INSTRUMENT_VARIABLE(diff);
+            BOOST_MATH_INSTRUMENT_VARIABLE(result);
+         }
+#endif
+      }
+      return round_x_from_p(x, p, result, fudge_factor, base, lim, discrete_quantile_type());
+   }
+   else
+   {
+      unsigned x = lim;
+      result = 0;
+      T diff = hypergeometric_pdf<T>(x, r, n, N, pol);
+      if (diff == 0)
+      {
+         // We want to skip through x values as fast as we can until we start getting non-zero values,
+         // otherwise we're just making lots of expensive PDF calls:
+         --x;
+         T log_pdf = boost::math::lgamma(static_cast<T>(n + 1), pol)
+            + boost::math::lgamma(static_cast<T>(r + 1), pol)
+            + boost::math::lgamma(static_cast<T>(N - n + 1), pol)
+            + boost::math::lgamma(static_cast<T>(N - r + 1), pol)
+            - boost::math::lgamma(static_cast<T>(N + 1), pol)
+            - boost::math::lgamma(static_cast<T>(x + 1), pol)
+            - boost::math::lgamma(static_cast<T>(n - x + 1), pol)
+            - boost::math::lgamma(static_cast<T>(r - x + 1), pol)
+            - boost::math::lgamma(static_cast<T>(N - n - r + x + 1), pol);
+         while (log_pdf < tools::log_min_value<T>())
+         {
+            log_pdf += log(static_cast<T>(x)) - log(static_cast<T>(n - x + 1)) - log(static_cast<T>(r - x + 1)) + log(static_cast<T>(N - n - r + x));
+            --x;
+         }
+         // By the time we get here, log_pdf may be fairly inaccurate due to
+         // roundoff errors, get a fresh PDF calculation before proceding:
+         diff = hypergeometric_pdf<T>(x, r, n, N, pol);
+      }
+      while(result + diff / 2 < q)
+      {
+         result += diff;
+         diff = (diff > tools::min_value<T>() * 8)
+            ? x * T(N + x - n - r) * diff / (T(1 + n - x) * T(1 + r - x))
+            : hypergeometric_pdf<T>(x - 1, r, n, N, pol);
+         --x;
+#ifdef BOOST_MATH_INSTRUMENT
+         if(diff != 0)
+         {
+            BOOST_MATH_INSTRUMENT_VARIABLE(x);
+            BOOST_MATH_INSTRUMENT_VARIABLE(diff);
+            BOOST_MATH_INSTRUMENT_VARIABLE(result);
+         }
+#endif
+      }
+      return round_x_from_q(x, q, result, fudge_factor, base, lim, discrete_quantile_type());
+   }
+#ifdef BOOST_MSVC
+#  pragma warning(pop)
+#endif
+}
+
+template <class T, class Policy>
+inline unsigned hypergeometric_quantile(T p, T q, unsigned r, unsigned n, unsigned N, const Policy&)
+{
+   BOOST_FPU_EXCEPTION_GUARD
+   typedef typename tools::promote_args<T>::type result_type;
+   typedef typename policies::evaluation<result_type, Policy>::type value_type;
+   typedef typename policies::normalise<
+      Policy, 
+      policies::promote_float<false>, 
+      policies::promote_double<false>, 
+      policies::assert_undefined<> >::type forwarding_policy;
+
+   return detail::hypergeometric_quantile_imp<value_type>(p, q, r, n, N, forwarding_policy());
+}
+
+}}} // namespaces
+
+#endif
+