From f3afc63127880c397839549e52c7877ffd518b52 Mon Sep 17 00:00:00 2001
From: swagata87 <physics.swagata@gmail.com>
Date: Wed, 31 Aug 2022 04:30:52 +0200
Subject: [PATCH] add only meaningful states

---
 TrackingTools/GsfTracking/src/GsfMultiStateUpdator.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/TrackingTools/GsfTracking/src/GsfMultiStateUpdator.cc b/TrackingTools/GsfTracking/src/GsfMultiStateUpdator.cc
index c3958e7f0c48f..5e9e6b3138924 100644
--- a/TrackingTools/GsfTracking/src/GsfMultiStateUpdator.cc
+++ b/TrackingTools/GsfTracking/src/GsfMultiStateUpdator.cc
@@ -30,7 +30,10 @@ TrajectoryStateOnSurface GsfMultiStateUpdator::update(const TrajectoryStateOnSur
   int i = 0;
   for (auto const& tsosI : predictedComponents) {
     TrajectoryStateOnSurface updatedTSOS = KFUpdator().update(tsosI, aRecHit);
-    if (updatedTSOS.isValid() && updatedTSOS.localError().valid()) {
+
+    double det = 0;
+    if (updatedTSOS.isValid() && updatedTSOS.localError().valid() && updatedTSOS.localError().posDef() &&
+        (updatedTSOS.curvilinearError().matrix().Det2(det)) && det > 0) {
       result.addState(TrajectoryStateOnSurface(weights[i],
                                                updatedTSOS.localParameters(),
                                                updatedTSOS.localError(),