From 787256c4df0edfd6774127babeab329c36b9ce8b Mon Sep 17 00:00:00 2001 From: Ven Popov Date: Sat, 23 Mar 2024 07:51:06 +0100 Subject: [PATCH 1/2] fixes #3035 by using log_modified_bessel to improve stability --- stan/math/prim/prob/von_mises_lpdf.hpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/stan/math/prim/prob/von_mises_lpdf.hpp b/stan/math/prim/prob/von_mises_lpdf.hpp index f8e5e1aa303..c397137eb58 100644 --- a/stan/math/prim/prob/von_mises_lpdf.hpp +++ b/stan/math/prim/prob/von_mises_lpdf.hpp @@ -81,8 +81,8 @@ return_type_t von_mises_lpdf(T_y const& y, T_loc const& mu, if (!is_constant_all::value) { edge<2>(ops_partials).partials_ = cos_mu_minus_y - - modified_bessel_first_kind(1, kappa_val) - / modified_bessel_first_kind(0, kappa_val); + - exp(log_modified_bessel_first_kind(1, kappa_val) + - log_modified_bessel_first_kind(0, kappa_val)); } return ops_partials.build(logp); From 76dea25cb7f1a0447cae2a9c99e405e294a701df Mon Sep 17 00:00:00 2001 From: Stan Jenkins Date: Sat, 23 Mar 2024 03:18:41 -0400 Subject: [PATCH 2/2] [Jenkins] auto-formatting by clang-format version 10.0.0-4ubuntu1 --- stan/math/prim/prob/von_mises_lpdf.hpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/stan/math/prim/prob/von_mises_lpdf.hpp b/stan/math/prim/prob/von_mises_lpdf.hpp index c397137eb58..7a759d9f43d 100644 --- a/stan/math/prim/prob/von_mises_lpdf.hpp +++ b/stan/math/prim/prob/von_mises_lpdf.hpp @@ -82,7 +82,7 @@ return_type_t von_mises_lpdf(T_y const& y, T_loc const& mu, edge<2>(ops_partials).partials_ = cos_mu_minus_y - exp(log_modified_bessel_first_kind(1, kappa_val) - - log_modified_bessel_first_kind(0, kappa_val)); + - log_modified_bessel_first_kind(0, kappa_val)); } return ops_partials.build(logp);