1 #ifndef STAN_MATH_PRIM_SCAL_PROB_NEG_BINOMIAL_2_LOG_LPMF_HPP 2 #define STAN_MATH_PRIM_SCAL_PROB_NEG_BINOMIAL_2_LOG_LPMF_HPP 20 template <
bool propto,
typename T_n,
typename T_log_location,
23 const T_n& n,
const T_log_location& eta,
const T_precision& phi) {
26 T_precision>::type T_partials_return;
28 static const char*
function =
"neg_binomial_2_log_lpmf";
33 T_partials_return logp(0.0);
38 "Log location parameter", eta,
"Precision parameter",
58 for (
size_t i = 0, size =
length(eta); i <
size; ++i)
62 for (
size_t i = 0, size =
length(phi); i <
size; ++i)
66 for (
size_t i = 0, size =
length(phi); i <
size; ++i)
67 log_phi[i] =
log(phi__[i]);
70 logsumexp_eta_logphi(len_ep);
71 for (
size_t i = 0; i < len_ep; ++i)
72 logsumexp_eta_logphi[i] =
log_sum_exp(eta__[i], log_phi[i]);
75 for (
size_t i = 0; i < len_np; ++i)
76 n_plus_phi[i] = n_vec[i] + phi__[i];
78 for (
size_t i = 0; i <
size; i++) {
80 logp -=
lgamma(n_vec[i] + 1.0);
84 logp -= (n_plus_phi[i]) * logsumexp_eta_logphi[i];
86 logp += n_vec[i] * eta__[i];
88 logp +=
lgamma(n_plus_phi[i]);
91 ops_partials.
edge1_.partials_[i]
92 += n_vec[i] - n_plus_phi[i] / (phi__[i] /
exp(eta__[i]) + 1.0);
94 ops_partials.
edge2_.partials_[i]
95 += 1.0 - n_plus_phi[i] / (
exp(eta__[i]) + phi__[i]) + log_phi[i]
96 - logsumexp_eta_logphi[i] -
digamma(phi__[i])
99 return ops_partials.
build(logp);
102 template <
typename T_n,
typename T_log_location,
typename T_precision>
105 const T_precision& phi) {
106 return neg_binomial_2_log_lpmf<false>(n, eta, phi);
void check_finite(const char *function, const char *name, const T_y &y)
Check if y is finite.
fvar< T > lgamma(const fvar< T > &x)
Return the natural logarithm of the gamma function applied to the specified argument.
T value_of(const fvar< T > &v)
Return the value of the specified variable.
Extends std::true_type when instantiated with zero or more template parameters, all of which extend t...
fvar< T > log(const fvar< T > &x)
scalar_seq_view provides a uniform sequence-like wrapper around either a scalar or a sequence of scal...
This template builds partial derivatives with respect to a set of operands.
size_t length(const std::vector< T > &x)
Returns the length of the provided std::vector.
bool size_zero(T &x)
Returns 1 if input is of length 0, returns 0 otherwise.
fvar< T > log_sum_exp(const std::vector< fvar< T > > &v)
Template metaprogram to calculate whether a summand needs to be included in a proportional (log) prob...
void check_nonnegative(const char *function, const char *name, const T_y &y)
Check if y is non-negative.
void check_positive_finite(const char *function, const char *name, const T_y &y)
Check if y is positive and finite.
Template metaprogram to calculate the partial derivative type resulting from promoting all the scalar...
return_type< T_log_location, T_precision >::type neg_binomial_2_log_lpmf(const T_n &n, const T_log_location &eta, const T_precision &phi)
boost::math::tools::promote_args< double, typename scalar_type< T >::type, typename return_type< Types_pack... >::type >::type type
fvar< T > exp(const fvar< T > &x)
size_t max_size(const T1 &x1, const T2 &x2)
T_return_type build(double value)
Build the node to be stored on the autodiff graph.
fvar< T > multiply_log(const fvar< T > &x1, const fvar< T > &x2)
VectorBuilder allocates type T1 values to be used as intermediate values.
internal::ops_partials_edge< double, Op2 > edge2_
int size(const std::vector< T > &x)
Return the size of the specified standard vector.
void check_consistent_sizes(const char *function, const char *name1, const T1 &x1, const char *name2, const T2 &x2)
Check if the dimension of x1 is consistent with x2.
internal::ops_partials_edge< double, Op1 > edge1_
fvar< T > digamma(const fvar< T > &x)
Return the derivative of the log gamma function at the specified argument.