From c438126b872116d65395054c20e09df88c1cd09a Mon Sep 17 00:00:00 2001
From: Joschka Roffe <joshuaroffe@gmail.com>
Date: Tue, 17 Jun 2025 19:26:18 +0100
Subject: [PATCH] chore: bump version to 2.3.7 in pyproject.toml; update
 ms_scaling_factor handling in bp.hpp; add empty test file for bp_serial

---
 pyproject.toml                |  2 +-
 python_test/test_bp_serial.py |  0
 python_test/test_qcodes.py    |  4 ++--
 src_cpp/bp.hpp                | 13 +++++++------
 4 files changed, 10 insertions(+), 9 deletions(-)
 create mode 100644 python_test/test_bp_serial.py

diff --git a/pyproject.toml b/pyproject.toml
index a0d86e40..826b83a6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,7 +25,7 @@ dependencies = [
     "sinter>=1.12.0",
     "pymatching"
 ]
-version = "2.3.6"
+version = "2.3.7"
 
 [project.urls]
 Documentation = "https://software.roffe.eu/ldpc"
diff --git a/python_test/test_bp_serial.py b/python_test/test_bp_serial.py
new file mode 100644
index 00000000..e69de29b
diff --git a/python_test/test_qcodes.py b/python_test/test_qcodes.py
index 93a2f4fc..1a1bc961 100644
--- a/python_test/test_qcodes.py
+++ b/python_test/test_qcodes.py
@@ -239,7 +239,7 @@ def test_400_16_6_hgp():
         error_rate=error_rate,
         max_iter=max_iter,
         bp_method="ms",
-        ms_scaling_factor=0,
+        ms_scaling_factor=-1,
         schedule="parallel",
         bits_per_step=1,
         lsd_order=0,
@@ -260,7 +260,7 @@ def test_400_16_6_hgp():
         error_rate=error_rate,
         max_iter=max_iter,
         bp_method="ms",
-        ms_scaling_factor=0,
+        ms_scaling_factor=-1,
         schedule="serial",
         bits_per_step=1,
         lsd_order=0,
diff --git a/src_cpp/bp.hpp b/src_cpp/bp.hpp
index e5561c06..d3ac6eca 100644
--- a/src_cpp/bp.hpp
+++ b/src_cpp/bp.hpp
@@ -207,10 +207,10 @@ namespace ldpc {
                     } else if (this->bp_method == MINIMUM_SUM) {
 
                         double alpha;
-                        if(this->ms_scaling_factor == 0.0) {
-                            alpha = 1.0 - std::pow(2.0, -1.0*it);
-                        }
-                        else {
+                        if(this->ms_scaling_factor < 0.0) {
+                            double damping_factor = std::abs(this->ms_scaling_factor);
+                            alpha = 1.0 - std::pow(2.0, -1.0*it/damping_factor);
+                        } else {
                             alpha = this->ms_scaling_factor;
                         }
 
@@ -444,8 +444,9 @@ namespace ldpc {
                 for (int it = 1; it <= maximum_iterations; it++) {
 
                     double alpha;
-                    if(this->ms_scaling_factor == 0.0) {
-                        alpha = 1.0 - std::pow(2.0, -1.0*it);
+                    if(this->ms_scaling_factor < 0.0) {
+                        double damping_factor = std::abs(this->ms_scaling_factor);
+                        alpha = 1.0 - std::pow(2.0, -1.0*it/damping_factor);
                     }
                     else {
                         alpha = this->ms_scaling_factor;