From d6b112d4ccda8e560f91e19e215f32fe4b8cee15 Mon Sep 17 00:00:00 2001
From: Andreas Stefl <stefl.andreas@gmail.com>
Date: Thu, 29 Aug 2024 11:10:13 +0200
Subject: [PATCH] refactor: Remove `calculateTrackQuantities` from Core CKF
 (#3567)

Originally https://github.com/acts-project/acts/pull/3536 but reverted with https://github.com/acts-project/acts/pull/3565 due to FPEs in Athena.

---

Remove `calculateTrackQuantities` which recalculates measurements and holes from the track since we already accumulate these numbers inside the CKF actor.
---
 .../include/Acts/TrackFinding/CombinatorialKalmanFilter.hpp | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/Core/include/Acts/TrackFinding/CombinatorialKalmanFilter.hpp b/Core/include/Acts/TrackFinding/CombinatorialKalmanFilter.hpp
index 7156160a6064..34dabcd343de 100644
--- a/Core/include/Acts/TrackFinding/CombinatorialKalmanFilter.hpp
+++ b/Core/include/Acts/TrackFinding/CombinatorialKalmanFilter.hpp
@@ -982,6 +982,8 @@ class CombinatorialKalmanFilter {
           typeFlags.set(TrackStateFlag::MeasurementFlag);
           // Increment number of measurements
           newBranch.nMeasurements()++;
+          newBranch.nDoF() += trackState.calibratedSize();
+          newBranch.chi2() += trackState.chi2();
         } else {
           ACTS_WARNING("Cannot handle this track state flags");
           continue;
@@ -1330,10 +1332,6 @@ class CombinatorialKalmanFilter {
       return error.error();
     }
 
-    for (const auto& track : combKalmanResult.collectedTracks) {
-      calculateTrackQuantities(track);
-    }
-
     return std::move(combKalmanResult.collectedTracks);
   }
 };