1 #ifndef STAN_MATH_PRIM_SCAL_PROB_RAYLEIGH_LPDF_HPP 2 #define STAN_MATH_PRIM_SCAL_PROB_RAYLEIGH_LPDF_HPP 16 template <
bool propto,
typename T_y,
typename T_scale>
18 const T_scale& sigma) {
19 static const char*
function =
"rayleigh_lpdf";
28 T_partials_return logp(0.0);
49 for (
size_t i = 0; i <
length(sigma); i++) {
50 inv_sigma[i] = 1.0 /
value_of(sigma_vec[i]);
55 for (
size_t n = 0; n < N; n++) {
56 const T_partials_return y_dbl =
value_of(y_vec[n]);
57 const T_partials_return y_over_sigma = y_dbl * inv_sigma[n];
58 static double NEGATIVE_HALF = -0.5;
61 logp -= 2.0 * log_sigma[n];
64 logp += NEGATIVE_HALF * y_over_sigma * y_over_sigma;
66 T_partials_return scaled_diff = inv_sigma[n] * y_over_sigma;
68 ops_partials.
edge1_.partials_[n] += 1.0 / y_dbl - scaled_diff;
70 ops_partials.
edge2_.partials_[n]
71 += y_over_sigma * scaled_diff - 2.0 * inv_sigma[n];
73 return ops_partials.
build(logp);
76 template <
typename T_y,
typename T_scale>
78 const T_y& y,
const T_scale& sigma) {
79 return rayleigh_lpdf<false>(y, sigma);
boost::math::tools::promote_args< double, typename partials_type< typename scalar_type< T >::type >::type, typename partials_return_type< T_pack... >::type >::type type
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.
Template metaprogram to calculate whether a summand needs to be included in a proportional (log) prob...
boost::math::tools::promote_args< double, typename scalar_type< T >::type, typename return_type< Types_pack... >::type >::type type
void check_not_nan(const char *function, const char *name, const T_y &y)
Check if y is not NaN.
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.
VectorBuilder allocates type T1 values to be used as intermediate values.
internal::ops_partials_edge< double, Op2 > edge2_
void check_positive(const char *function, const char *name, const T_y &y)
Check if y is positive.
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.
return_type< T_y, T_scale >::type rayleigh_lpdf(const T_y &y, const T_scale &sigma)
internal::ops_partials_edge< double, Op1 > edge1_