From 4e6a527ce299c28ec27ab80306ef7005d975f3a7 Mon Sep 17 00:00:00 2001
From: Matt Graham <matthew.m.graham@gmail.com>
Date: Wed, 23 Oct 2024 16:48:08 +0100
Subject: [PATCH] Fix sign error in log density ratio for Langevin proposal
 (#41)

---
 R/langevin.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/langevin.R b/R/langevin.R
index 9117d52..853cd9e 100644
--- a/R/langevin.R
+++ b/R/langevin.R
@@ -44,7 +44,7 @@ log_density_ratio_langevin <- function(
     proposed_state,
     target_distribution,
     scale_and_shape) {
-  sum(proposed_state$momentum()^2 - state$momentum()^2) / 2
+  sum(state$momentum()^2 - proposed_state$momentum()^2) / 2
 }
 
 #' Create a new Langevin proposal object.