1 #ifndef STAN_MATH_PRIM_SCAL_PROB_VON_MISES_LOG_HPP
2 #define STAN_MATH_PRIM_SCAL_PROB_VON_MISES_LOG_HPP
24 typename T_y,
typename T_loc,
typename T_scale>
25 typename return_type<T_y, T_loc, T_scale>::type
27 static char const*
const function =
"stan::math::von_mises_log";
49 T_partials_return logp = 0.0;
57 "Location parameter", mu,
58 "Scale parameter", kappa);
72 const bool compute_bessel1 = !kappa_const;
82 T_partials_return, T_scale> log_bessel0(
length(kappa));
83 for (
size_t i = 0; i <
length(kappa); i++) {
84 kappa_dbl[i] =
value_of(kappa_vec[i]);
94 for (
size_t n = 0; n < N; n++) {
96 const T_partials_return
y_ =
value_of(y_vec[n]);
97 const T_partials_return y_dbl = y_ -
floor(y_ / TWO_PI) * TWO_PI;
98 const T_partials_return mu_dbl =
value_of(mu_vec[n]);
101 T_partials_return bessel0 = 0;
104 T_partials_return bessel1 = 0;
107 const T_partials_return kappa_sin = kappa_dbl[n] *
sin(mu_dbl - y_dbl);
108 const T_partials_return kappa_cos = kappa_dbl[n] *
cos(mu_dbl - y_dbl);
114 logp -= log_bessel0[n];
120 oap.
d_x1[n] += kappa_sin;
122 oap.
d_x2[n] -= kappa_sin;
124 oap.
d_x3[n] += kappa_cos / kappa_dbl[n] - bessel1 / bessel0;
127 return oap.
to_var(logp, y, mu, kappa);
130 template<
typename T_y,
typename T_loc,
typename T_scale>
133 return von_mises_log<false>(y, mu, kappa);
fvar< T > cos(const fvar< T > &x)
T value_of(const fvar< T > &v)
Return the value of the specified variable.
fvar< T > log(const fvar< T > &x)
size_t length(const std::vector< T > &x)
T_return_type to_var(T_partials_return logp, const T1 &x1=0, const T2 &x2=0, const T3 &x3=0, const T4 &x4=0, const T5 &x5=0, const T6 &x6=0)
Template metaprogram to calculate whether a summand needs to be included in a proportional (log) prob...
boost::math::tools::promote_args< typename scalar_type< T1 >::type, typename scalar_type< T2 >::type, typename scalar_type< T3 >::type, typename scalar_type< T4 >::type, typename scalar_type< T5 >::type, typename scalar_type< T6 >::type >::type type
VectorView< T_partials_return, is_vector< T1 >::value, is_constant_struct< T1 >::value > d_x1
Metaprogram to determine if a type has a base scalar type that can be assigned to type double...
fvar< T > modified_bessel_first_kind(int v, const fvar< T > &z)
fvar< T > sin(const fvar< T > &x)
return_type< T_y, T_loc, T_scale >::type von_mises_log(T_y const &y, T_loc const &mu, T_scale const &kappa)
VectorView< T_partials_return, is_vector< T3 >::value, is_constant_struct< T3 >::value > d_x3
A variable implementation that stores operands and derivatives with respect to the variable...
size_t max_size(const T1 &x1, const T2 &x2)
bool check_finite(const char *function, const char *name, const T_y &y)
Return true if y is finite.
fvar< T > floor(const fvar< T > &x)
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.
VectorView< T_partials_return, is_vector< T2 >::value, is_constant_struct< T2 >::value > d_x2
double pi()
Return the value of pi.
bool check_nonnegative(const char *function, const char *name, const T_y &y)
Return true if y is non-negative.
VectorView is a template metaprogram that takes its argument and allows it to be used like a vector...
boost::math::tools::promote_args< typename partials_type< typename scalar_type< T1 >::type >::type, typename partials_type< typename scalar_type< T2 >::type >::type, typename partials_type< typename scalar_type< T3 >::type >::type, typename partials_type< typename scalar_type< T4 >::type >::type, typename partials_type< typename scalar_type< T5 >::type >::type, typename partials_type< typename scalar_type< T6 >::type >::type >::type type
bool check_positive_finite(const char *function, const char *name, const T_y &y)
Return true if y is positive and finite.
bool check_greater(const char *function, const char *name, const T_y &y, const T_low &low)
Return true if y is strictly greater than low.