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1// boost\math\special_functions\negative_binomial.hpp2 3// Copyright Paul A. Bristow 2007.4// Copyright John Maddock 2007.5 6// Use, modification and distribution are subject to the7// Boost Software License, Version 1.0.8// (See accompanying file LICENSE_1_0.txt9// or copy at http://www.boost.org/LICENSE_1_0.txt)10 11// http://en.wikipedia.org/wiki/negative_binomial_distribution12// http://mathworld.wolfram.com/NegativeBinomialDistribution.html13// http://documents.wolfram.com/teachersedition/Teacher/Statistics/DiscreteDistributions.html14 15// The negative binomial distribution NegativeBinomialDistribution[n, p]16// is the distribution of the number (k) of failures that occur in a sequence of trials before17// r successes have occurred, where the probability of success in each trial is p.18 19// In a sequence of Bernoulli trials or events20// (independent, yes or no, succeed or fail) with success_fraction probability p,21// negative_binomial is the probability that k or fewer failures22// precede the r th trial's success.23// random variable k is the number of failures (NOT the probability).24 25// Negative_binomial distribution is a discrete probability distribution.26// But note that the negative binomial distribution27// (like others including the binomial, Poisson & Bernoulli)28// is strictly defined as a discrete function: only integral values of k are envisaged.29// However because of the method of calculation using a continuous gamma function,30// it is convenient to treat it as if a continuous function,31// and permit non-integral values of k.32 33// However, by default the policy is to use discrete_quantile_policy.34 35// To enforce the strict mathematical model, users should use conversion36// on k outside this function to ensure that k is integral.37 38// MATHCAD cumulative negative binomial pnbinom(k, n, p)39 40// Implementation note: much greater speed, and perhaps greater accuracy,41// might be achieved for extreme values by using a normal approximation.42// This is NOT been tested or implemented.43 44#ifndef BOOST_MATH_SPECIAL_NEGATIVE_BINOMIAL_HPP45#define BOOST_MATH_SPECIAL_NEGATIVE_BINOMIAL_HPP46 47#include <boost/math/tools/config.hpp>48#include <boost/math/tools/tuple.hpp>49#include <boost/math/tools/numeric_limits.hpp>50#include <boost/math/tools/cstdint.hpp>51#include <boost/math/distributions/fwd.hpp>52#include <boost/math/special_functions/beta.hpp> // for ibeta(a, b, x) == Ix(a, b).53#include <boost/math/distributions/complement.hpp> // complement.54#include <boost/math/distributions/detail/common_error_handling.hpp> // error checks domain_error & logic_error.55#include <boost/math/special_functions/fpclassify.hpp> // isnan.56#include <boost/math/tools/roots.hpp> // for root finding.57#include <boost/math/distributions/detail/inv_discrete_quantile.hpp>58#include <boost/math/policies/error_handling.hpp>59 60#if defined (BOOST_MSVC)61#  pragma warning(push)62// This believed not now necessary, so commented out.63//#  pragma warning(disable: 4702) // unreachable code.64// in domain_error_imp in error_handling.65#endif66 67namespace boost68{69  namespace math70  {71    namespace negative_binomial_detail72    {73      // Common error checking routines for negative binomial distribution functions:74      template <class RealType, class Policy>75      BOOST_MATH_GPU_ENABLED inline bool check_successes(const char* function, const RealType& r, RealType* result, const Policy& pol)76      {77        if( !(boost::math::isfinite)(r) || (r <= 0) )78        {79          *result = policies::raise_domain_error<RealType>(80            function,81            "Number of successes argument is %1%, but must be > 0 !", r, pol);82          return false;83        }84        return true;85      }86      template <class RealType, class Policy>87      BOOST_MATH_GPU_ENABLED inline bool check_success_fraction(const char* function, const RealType& p, RealType* result, const Policy& pol)88      {89        if( !(boost::math::isfinite)(p) || (p < 0) || (p > 1) )90        {91          *result = policies::raise_domain_error<RealType>(92            function,93            "Success fraction argument is %1%, but must be >= 0 and <= 1 !", p, pol);94          return false;95        }96        return true;97      }98      template <class RealType, class Policy>99      BOOST_MATH_GPU_ENABLED inline bool check_dist(const char* function, const RealType& r, const RealType& p, RealType* result, const Policy& pol)100      {101        return check_success_fraction(function, p, result, pol)102          && check_successes(function, r, result, pol);103      }104      template <class RealType, class Policy>105      BOOST_MATH_GPU_ENABLED inline bool check_dist_and_k(const char* function, const RealType& r, const RealType& p, RealType k, RealType* result, const Policy& pol)106      {107        if(check_dist(function, r, p, result, pol) == false)108        {109          return false;110        }111        if( !(boost::math::isfinite)(k) || (k < 0) )112        { // Check k failures.113          *result = policies::raise_domain_error<RealType>(114            function,115            "Number of failures argument is %1%, but must be >= 0 !", k, pol);116          return false;117        }118        return true;119      } // Check_dist_and_k120 121      template <class RealType, class Policy>122      BOOST_MATH_GPU_ENABLED inline bool check_dist_and_prob(const char* function, const RealType& r, RealType p, RealType prob, RealType* result, const Policy& pol)123      {124        if((check_dist(function, r, p, result, pol) && detail::check_probability(function, prob, result, pol)) == false)125        {126          return false;127        }128        return true;129      } // check_dist_and_prob130    } //  namespace negative_binomial_detail131 132    template <class RealType = double, class Policy = policies::policy<> >133    class negative_binomial_distribution134    {135    public:136      typedef RealType value_type;137      typedef Policy policy_type;138 139      BOOST_MATH_GPU_ENABLED negative_binomial_distribution(RealType r, RealType p) : m_r(r), m_p(p)140      { // Constructor.141        RealType result;142        negative_binomial_detail::check_dist(143          "negative_binomial_distribution<%1%>::negative_binomial_distribution",144          m_r, // Check successes r > 0.145          m_p, // Check success_fraction 0 <= p <= 1.146          &result, Policy());147      } // negative_binomial_distribution constructor.148 149      // Private data getter class member functions.150      BOOST_MATH_GPU_ENABLED RealType success_fraction() const151      { // Probability of success as fraction in range 0 to 1.152        return m_p;153      }154      BOOST_MATH_GPU_ENABLED RealType successes() const155      { // Total number of successes r.156        return m_r;157      }158 159      BOOST_MATH_GPU_ENABLED static RealType find_lower_bound_on_p(160        RealType trials,161        RealType successes,162        RealType alpha) // alpha 0.05 equivalent to 95% for one-sided test.163      {164        constexpr auto function = "boost::math::negative_binomial<%1%>::find_lower_bound_on_p";165        RealType result = 0;  // of error checks.166        RealType failures = trials - successes;167        if(false == detail::check_probability(function, alpha, &result, Policy())168          && negative_binomial_detail::check_dist_and_k(169          function, successes, RealType(0), failures, &result, Policy()))170        {171          return result;172        }173        // Use complement ibeta_inv function for lower bound.174        // This is adapted from the corresponding binomial formula175        // here: http://www.itl.nist.gov/div898/handbook/prc/section2/prc241.htm176        // This is a Clopper-Pearson interval, and may be overly conservative,177        // see also "A Simple Improved Inferential Method for Some178        // Discrete Distributions" Yong CAI and K. KRISHNAMOORTHY179        // http://www.ucs.louisiana.edu/~kxk4695/Discrete_new.pdf180        //181        return ibeta_inv(successes, failures + 1, alpha, static_cast<RealType*>(nullptr), Policy());182      } // find_lower_bound_on_p183 184      BOOST_MATH_GPU_ENABLED static RealType find_upper_bound_on_p(185        RealType trials,186        RealType successes,187        RealType alpha) // alpha 0.05 equivalent to 95% for one-sided test.188      {189        constexpr auto function = "boost::math::negative_binomial<%1%>::find_upper_bound_on_p";190        RealType result = 0;  // of error checks.191        RealType failures = trials - successes;192        if(false == negative_binomial_detail::check_dist_and_k(193          function, successes, RealType(0), failures, &result, Policy())194          && detail::check_probability(function, alpha, &result, Policy()))195        {196          return result;197        }198        if(failures == 0)199           return 1;200        // Use complement ibetac_inv function for upper bound.201        // Note adjusted failures value: *not* failures+1 as usual.202        // This is adapted from the corresponding binomial formula203        // here: http://www.itl.nist.gov/div898/handbook/prc/section2/prc241.htm204        // This is a Clopper-Pearson interval, and may be overly conservative,205        // see also "A Simple Improved Inferential Method for Some206        // Discrete Distributions" Yong CAI and K. KRISHNAMOORTHY207        // http://www.ucs.louisiana.edu/~kxk4695/Discrete_new.pdf208        //209        return ibetac_inv(successes, failures, alpha, static_cast<RealType*>(nullptr), Policy());210      } // find_upper_bound_on_p211 212      // Estimate number of trials :213      // "How many trials do I need to be P% sure of seeing k or fewer failures?"214 215      BOOST_MATH_GPU_ENABLED static RealType find_minimum_number_of_trials(216        RealType k,     // number of failures (k >= 0).217        RealType p,     // success fraction 0 <= p <= 1.218        RealType alpha) // risk level threshold 0 <= alpha <= 1.219      {220        constexpr auto function = "boost::math::negative_binomial<%1%>::find_minimum_number_of_trials";221        // Error checks:222        RealType result = 0;223        if(false == negative_binomial_detail::check_dist_and_k(224          function, RealType(1), p, k, &result, Policy())225          && detail::check_probability(function, alpha, &result, Policy()))226        { return result; }227 228        result = ibeta_inva(k + 1, p, alpha, Policy());  // returns n - k229        return result + k;230      } // RealType find_number_of_failures231 232      BOOST_MATH_GPU_ENABLED static RealType find_maximum_number_of_trials(233        RealType k,     // number of failures (k >= 0).234        RealType p,     // success fraction 0 <= p <= 1.235        RealType alpha) // risk level threshold 0 <= alpha <= 1.236      {237        constexpr auto function = "boost::math::negative_binomial<%1%>::find_maximum_number_of_trials";238        // Error checks:239        RealType result = 0;240        if(false == negative_binomial_detail::check_dist_and_k(241          function, RealType(1), p, k, &result, Policy())242          &&  detail::check_probability(function, alpha, &result, Policy()))243        { return result; }244 245        result = ibetac_inva(k + 1, p, alpha, Policy());  // returns n - k246        return result + k;247      } // RealType find_number_of_trials complemented248 249    private:250      RealType m_r; // successes.251      RealType m_p; // success_fraction252    }; // template <class RealType, class Policy> class negative_binomial_distribution253 254    typedef negative_binomial_distribution<double> negative_binomial; // Reserved name of type double.255 256    #ifdef __cpp_deduction_guides257    template <class RealType>258    negative_binomial_distribution(RealType,RealType)->negative_binomial_distribution<typename boost::math::tools::promote_args<RealType>::type>;259    #endif260 261    template <class RealType, class Policy>262    BOOST_MATH_GPU_ENABLED inline const boost::math::pair<RealType, RealType> range(const negative_binomial_distribution<RealType, Policy>& /* dist */)263    { // Range of permissible values for random variable k.264       using boost::math::tools::max_value;265       return boost::math::pair<RealType, RealType>(static_cast<RealType>(0), max_value<RealType>()); // max_integer?266    }267 268    template <class RealType, class Policy>269    BOOST_MATH_GPU_ENABLED inline const boost::math::pair<RealType, RealType> support(const negative_binomial_distribution<RealType, Policy>& /* dist */)270    { // Range of supported values for random variable k.271       // This is range where cdf rises from 0 to 1, and outside it, the pdf is zero.272       using boost::math::tools::max_value;273       return boost::math::pair<RealType, RealType>(static_cast<RealType>(0),  max_value<RealType>()); // max_integer?274    }275 276    template <class RealType, class Policy>277    BOOST_MATH_GPU_ENABLED inline RealType mean(const negative_binomial_distribution<RealType, Policy>& dist)278    { // Mean of Negative Binomial distribution = r(1-p)/p.279      return dist.successes() * (1 - dist.success_fraction() ) / dist.success_fraction();280    } // mean281 282    //template <class RealType, class Policy>283    //inline RealType median(const negative_binomial_distribution<RealType, Policy>& dist)284    //{ // Median of negative_binomial_distribution is not defined.285    //  return policies::raise_domain_error<RealType>(BOOST_CURRENT_FUNCTION, "Median is not implemented, result is %1%!", std::numeric_limits<RealType>::quiet_NaN());286    //} // median287    // Now implemented via quantile(half) in derived accessors.288 289    template <class RealType, class Policy>290    BOOST_MATH_GPU_ENABLED inline RealType mode(const negative_binomial_distribution<RealType, Policy>& dist)291    { // Mode of Negative Binomial distribution = floor[(r-1) * (1 - p)/p]292      BOOST_MATH_STD_USING // ADL of std functions.293      return floor((dist.successes() -1) * (1 - dist.success_fraction()) / dist.success_fraction());294    } // mode295 296    template <class RealType, class Policy>297    BOOST_MATH_GPU_ENABLED inline RealType skewness(const negative_binomial_distribution<RealType, Policy>& dist)298    { // skewness of Negative Binomial distribution = 2-p / (sqrt(r(1-p))299      BOOST_MATH_STD_USING // ADL of std functions.300      RealType p = dist.success_fraction();301      RealType r = dist.successes();302 303      return (2 - p) /304        sqrt(r * (1 - p));305    } // skewness306 307    template <class RealType, class Policy>308    BOOST_MATH_GPU_ENABLED inline RealType kurtosis(const negative_binomial_distribution<RealType, Policy>& dist)309    { // kurtosis of Negative Binomial distribution310      // http://en.wikipedia.org/wiki/Negative_binomial is kurtosis_excess so add 3311      RealType p = dist.success_fraction();312      RealType r = dist.successes();313      return 3 + (6 / r) + ((p * p) / (r * (1 - p)));314    } // kurtosis315 316     template <class RealType, class Policy>317    BOOST_MATH_GPU_ENABLED inline RealType kurtosis_excess(const negative_binomial_distribution<RealType, Policy>& dist)318    { // kurtosis excess of Negative Binomial distribution319      // http://mathworld.wolfram.com/Kurtosis.html table of kurtosis_excess320      RealType p = dist.success_fraction();321      RealType r = dist.successes();322      return (6 - p * (6-p)) / (r * (1-p));323    } // kurtosis_excess324 325    template <class RealType, class Policy>326    BOOST_MATH_GPU_ENABLED inline RealType variance(const negative_binomial_distribution<RealType, Policy>& dist)327    { // Variance of Binomial distribution = r (1-p) / p^2.328      return  dist.successes() * (1 - dist.success_fraction())329        / (dist.success_fraction() * dist.success_fraction());330    } // variance331 332    // RealType standard_deviation(const negative_binomial_distribution<RealType, Policy>& dist)333    // standard_deviation provided by derived accessors.334    // RealType hazard(const negative_binomial_distribution<RealType, Policy>& dist)335    // hazard of Negative Binomial distribution provided by derived accessors.336    // RealType chf(const negative_binomial_distribution<RealType, Policy>& dist)337    // chf of Negative Binomial distribution provided by derived accessors.338 339    template <class RealType, class Policy>340    BOOST_MATH_GPU_ENABLED inline RealType pdf(const negative_binomial_distribution<RealType, Policy>& dist, const RealType& k)341    { // Probability Density/Mass Function.342      BOOST_FPU_EXCEPTION_GUARD343 344      constexpr auto function = "boost::math::pdf(const negative_binomial_distribution<%1%>&, %1%)";345 346      RealType r = dist.successes();347      RealType p = dist.success_fraction();348      RealType result = 0;349      if(false == negative_binomial_detail::check_dist_and_k(350        function,351        r,352        dist.success_fraction(),353        k,354        &result, Policy()))355      {356        return result;357      }358 359      result = (p/(r + k)) * ibeta_derivative(r, static_cast<RealType>(k+1), p, Policy());360      // Equivalent to:361      // return exp(lgamma(r + k) - lgamma(r) - lgamma(k+1)) * pow(p, r) * pow((1-p), k);362      return result;363    } // negative_binomial_pdf364 365    template <class RealType, class Policy>366    BOOST_MATH_GPU_ENABLED inline RealType cdf(const negative_binomial_distribution<RealType, Policy>& dist, const RealType& k)367    { // Cumulative Distribution Function of Negative Binomial.368      constexpr auto function = "boost::math::cdf(const negative_binomial_distribution<%1%>&, %1%)";369      using boost::math::ibeta; // Regularized incomplete beta function.370      // k argument may be integral, signed, or unsigned, or floating point.371      // If necessary, it has already been promoted from an integral type.372      RealType p = dist.success_fraction();373      RealType r = dist.successes();374      // Error check:375      RealType result = 0;376      if(false == negative_binomial_detail::check_dist_and_k(377        function,378        r,379        dist.success_fraction(),380        k,381        &result, Policy()))382      {383        return result;384      }385 386      RealType probability = ibeta(r, static_cast<RealType>(k+1), p, Policy());387      // Ip(r, k+1) = ibeta(r, k+1, p)388      return probability;389    } // cdf Cumulative Distribution Function Negative Binomial.390 391      template <class RealType, class Policy>392      BOOST_MATH_GPU_ENABLED inline RealType cdf(const complemented2_type<negative_binomial_distribution<RealType, Policy>, RealType>& c)393      { // Complemented Cumulative Distribution Function Negative Binomial.394 395      constexpr auto function = "boost::math::cdf(const negative_binomial_distribution<%1%>&, %1%)";396      using boost::math::ibetac; // Regularized incomplete beta function complement.397      // k argument may be integral, signed, or unsigned, or floating point.398      // If necessary, it has already been promoted from an integral type.399      RealType const& k = c.param;400      negative_binomial_distribution<RealType, Policy> const& dist = c.dist;401      RealType p = dist.success_fraction();402      RealType r = dist.successes();403      // Error check:404      RealType result = 0;405      if(false == negative_binomial_detail::check_dist_and_k(406        function,407        r,408        p,409        k,410        &result, Policy()))411      {412        return result;413      }414      // Calculate cdf negative binomial using the incomplete beta function.415      // Use of ibeta here prevents cancellation errors in calculating416      // 1-p if p is very small, perhaps smaller than machine epsilon.417      // Ip(k+1, r) = ibetac(r, k+1, p)418      // constrain_probability here?419     RealType probability = ibetac(r, static_cast<RealType>(k+1), p, Policy());420      // Numerical errors might cause probability to be slightly outside the range < 0 or > 1.421      // This might cause trouble downstream, so warn, possibly throw exception, but constrain to the limits.422      return probability;423    } // cdf Cumulative Distribution Function Negative Binomial.424 425    template <class RealType, class Policy>426    BOOST_MATH_GPU_ENABLED inline RealType quantile(const negative_binomial_distribution<RealType, Policy>& dist, const RealType& P)427    { // Quantile, percentile/100 or Percent Point Negative Binomial function.428      // Return the number of expected failures k for a given probability p.429 430      // Inverse cumulative Distribution Function or Quantile (percentile / 100) of negative_binomial Probability.431      // MAthCAD pnbinom return smallest k such that negative_binomial(k, n, p) >= probability.432      // k argument may be integral, signed, or unsigned, or floating point.433      // BUT Cephes/CodeCogs says: finds argument p (0 to 1) such that cdf(k, n, p) = y434      constexpr auto function = "boost::math::quantile(const negative_binomial_distribution<%1%>&, %1%)";435      BOOST_MATH_STD_USING // ADL of std functions.436 437      RealType p = dist.success_fraction();438      RealType r = dist.successes();439      // Check dist and P.440      RealType result = 0;441      if(false == negative_binomial_detail::check_dist_and_prob442        (function, r, p, P, &result, Policy()))443      {444        return result;445      }446 447      // Special cases.448      if (P == 1)449      {  // Would need +infinity failures for total confidence.450        result = policies::raise_overflow_error<RealType>(451            function,452            "Probability argument is 1, which implies infinite failures !", Policy());453        return result;454       // usually means return +std::numeric_limits<RealType>::infinity();455       // unless #define BOOST_MATH_THROW_ON_OVERFLOW_ERROR456      }457      if (P == 0)458      { // No failures are expected if P = 0.459        return 0; // Total trials will be just dist.successes.460      }461      if (P <= pow(dist.success_fraction(), dist.successes()))462      { // p <= pdf(dist, 0) == cdf(dist, 0)463        return 0;464      }465      if(p == 0)466      {  // Would need +infinity failures for total confidence.467         result = policies::raise_overflow_error<RealType>(468            function,469            "Success fraction is 0, which implies infinite failures !", Policy());470         return result;471         // usually means return +std::numeric_limits<RealType>::infinity();472         // unless #define BOOST_MATH_THROW_ON_OVERFLOW_ERROR473      }474      /*475      // Calculate quantile of negative_binomial using the inverse incomplete beta function.476      using boost::math::ibeta_invb;477      return ibeta_invb(r, p, P, Policy()) - 1; //478      */479      RealType guess = 0;480      RealType factor = 5;481      if(r * r * r * P * p > 0.005)482         guess = detail::inverse_negative_binomial_cornish_fisher(r, p, RealType(1-p), P, RealType(1-P), Policy());483 484      if(guess < 10)485      {486         //487         // Cornish-Fisher Negative binomial approximation not accurate in this area:488         //489         guess = BOOST_MATH_GPU_SAFE_MIN(RealType(r * 2), RealType(10));490      }491      else492         factor = (1-P < sqrt(tools::epsilon<RealType>())) ? 2 : (guess < 20 ? 1.2f : 1.1f);493      BOOST_MATH_INSTRUMENT_CODE("guess = " << guess);494      //495      // Max iterations permitted:496      //497      boost::math::uintmax_t max_iter = policies::get_max_root_iterations<Policy>();498      typedef typename Policy::discrete_quantile_type discrete_type;499      return detail::inverse_discrete_quantile(500         dist,501         P,502         false,503         guess,504         factor,505         RealType(1),506         discrete_type(),507         max_iter);508    } // RealType quantile(const negative_binomial_distribution dist, p)509 510    template <class RealType, class Policy>511    BOOST_MATH_GPU_ENABLED inline RealType quantile(const complemented2_type<negative_binomial_distribution<RealType, Policy>, RealType>& c)512    {  // Quantile or Percent Point Binomial function.513       // Return the number of expected failures k for a given514       // complement of the probability Q = 1 - P.515       constexpr auto function = "boost::math::quantile(const negative_binomial_distribution<%1%>&, %1%)";516       BOOST_MATH_STD_USING517 518       // Error checks:519       RealType Q = c.param;520       const negative_binomial_distribution<RealType, Policy>& dist = c.dist;521       RealType p = dist.success_fraction();522       RealType r = dist.successes();523       RealType result = 0;524       if(false == negative_binomial_detail::check_dist_and_prob(525          function,526          r,527          p,528          Q,529          &result, Policy()))530       {531          return result;532       }533 534       // Special cases:535       //536       if(Q == 1)537       {  // There may actually be no answer to this question,538          // since the probability of zero failures may be non-zero,539          return 0; // but zero is the best we can do:540       }541       if(Q == 0)542       {  // Probability 1 - Q  == 1 so infinite failures to achieve certainty.543          // Would need +infinity failures for total confidence.544          result = policies::raise_overflow_error<RealType>(545             function,546             "Probability argument complement is 0, which implies infinite failures !", Policy());547          return result;548          // usually means return +std::numeric_limits<RealType>::infinity();549          // unless #define BOOST_MATH_THROW_ON_OVERFLOW_ERROR550       }551       if (-Q <= boost::math::powm1(dist.success_fraction(), dist.successes(), Policy()))552       {  // q <= cdf(complement(dist, 0)) == pdf(dist, 0)553          return 0; //554       }555       if(p == 0)556       {  // Success fraction is 0 so infinite failures to achieve certainty.557          // Would need +infinity failures for total confidence.558          result = policies::raise_overflow_error<RealType>(559             function,560             "Success fraction is 0, which implies infinite failures !", Policy());561          return result;562          // usually means return +std::numeric_limits<RealType>::infinity();563          // unless #define BOOST_MATH_THROW_ON_OVERFLOW_ERROR564       }565       //return ibetac_invb(r, p, Q, Policy()) -1;566       RealType guess = 0;567       RealType factor = 5;568       if(r * r * r * (1-Q) * p > 0.005)569          guess = detail::inverse_negative_binomial_cornish_fisher(r, p, RealType(1-p), RealType(1-Q), Q, Policy());570 571       if(guess < 10)572       {573          //574          // Cornish-Fisher Negative binomial approximation not accurate in this area:575          //576          guess = BOOST_MATH_GPU_SAFE_MIN(RealType(r * 2), RealType(10));577       }578       else579          factor = (Q < sqrt(tools::epsilon<RealType>())) ? 2 : (guess < 20 ? 1.2f : 1.1f);580       BOOST_MATH_INSTRUMENT_CODE("guess = " << guess);581       //582       // Max iterations permitted:583       //584       boost::math::uintmax_t max_iter = policies::get_max_root_iterations<Policy>();585       typedef typename Policy::discrete_quantile_type discrete_type;586       return detail::inverse_discrete_quantile(587          dist,588          Q,589          true,590          guess,591          factor,592          RealType(1),593          discrete_type(),594          max_iter);595    } // quantile complement596 597 } // namespace math598} // namespace boost599 600// This include must be at the end, *after* the accessors601// for this distribution have been defined, in order to602// keep compilers that support two-phase lookup happy.603#include <boost/math/distributions/detail/derived_accessors.hpp>604 605#if defined (BOOST_MSVC)606# pragma warning(pop)607#endif608 609#endif // BOOST_MATH_SPECIAL_NEGATIVE_BINOMIAL_HPP610