Stan Math Library  2.9.0
reverse mode automatic differentiation
neg_binomial_2_cdf_log.hpp
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1 #ifndef STAN_MATH_PRIM_SCAL_PROB_NEG_BINOMIAL_2_CDF_LOG_HPP
2 #define STAN_MATH_PRIM_SCAL_PROB_NEG_BINOMIAL_2_CDF_LOG_HPP
3 
18 #include <boost/math/special_functions/digamma.hpp>
19 #include <boost/random/negative_binomial_distribution.hpp>
20 #include <boost/random/variate_generator.hpp>
21 #include <cmath>
22 #include <vector>
23 
24 namespace stan {
25 
26  namespace math {
27 
28  template <typename T_n, typename T_location,
29  typename T_precision>
30  typename return_type<T_location, T_precision>::type
31  neg_binomial_2_cdf_log(const T_n& n,
32  const T_location& mu,
33  const T_precision& phi) {
34  // Size checks
35  if ( !( stan::length(n) && stan::length(mu)
36  && stan::length(phi) ) )
37  return 0.0;
38 
44  using std::log;
45  using std::log;
46 
47  static const char* function("stan::math::neg_binomial_2_cdf");
48  check_positive_finite(function, "Location parameter", mu);
49  check_positive_finite(function, "Precision parameter", phi);
50  check_not_nan(function, "Random variable", n);
51  check_consistent_sizes(function,
52  "Random variable", n,
53  "Location parameter", mu,
54  "Precision Parameter", phi);
55 
56  VectorView<const T_n> n_vec(n);
58  VectorView<const T_precision> phi_vec(phi);
59 
60  size_t size_phi_mu = max_size(mu, phi);
61  size_t size_n = length(n);
62 
63  std::vector<typename return_type<T_location, T_precision>::type>
64  phi_mu(size_phi_mu);
65  std::vector<typename return_type<T_n>::type> np1(size_n);
66 
67  for (size_t i = 0; i < size_phi_mu; i++)
68  phi_mu[i] = phi_vec[i]/(phi_vec[i]+mu_vec[i]);
69 
70  for (size_t i = 0; i < size_n; i++)
71  if (n_vec[i] < 0)
72  return log(0.0);
73  else
74  np1[i] = n_vec[i] + 1.0;
75 
76  if (size_n == 1) {
77  if (size_phi_mu == 1)
78  return beta_cdf_log(phi_mu[0], phi, np1[0]);
79  else
80  return beta_cdf_log(phi_mu, phi, np1[0]);
81  } else {
82  if (size_phi_mu == 1)
83  return beta_cdf_log(phi_mu[0], phi, np1);
84  else
85  return beta_cdf_log(phi_mu, phi, np1);
86  }
87  }
88  }
89 }
90 #endif
bool check_less(const char *function, const char *name, const T_y &y, const T_high &high)
Return true if y is strictly less than high.
Definition: check_less.hpp:81
bool check_not_nan(const char *function, const char *name, const T_y &y)
Return true if y is not NaN.
fvar< T > log(const fvar< T > &x)
Definition: log.hpp:15
size_t length(const std::vector< T > &x)
Definition: length.hpp:10
size_t max_size(const T1 &x1, const T2 &x2)
Definition: max_size.hpp:9
return_type< T_y, T_scale_succ, T_scale_fail >::type beta_cdf_log(const T_y &y, const T_scale_succ &alpha, const T_scale_fail &beta)
bool check_consistent_sizes(const char *function, const char *name1, const T1 &x1, const char *name2, const T2 &x2)
Return true if the dimension of x1 is consistent with x2.
bool check_nonnegative(const char *function, const char *name, const T_y &y)
Return true if y is non-negative.
return_type< T_location, T_precision >::type neg_binomial_2_cdf_log(const T_n &n, const T_location &mu, const T_precision &phi)
VectorView is a template metaprogram that takes its argument and allows it to be used like a vector...
Definition: VectorView.hpp:41
bool check_positive_finite(const char *function, const char *name, const T_y &y)
Return true if y is positive and finite.

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