TrackDistanceValueMapProducer: check the size of the reference vector…

… before copying
cms-sw · May 6, 2021 · 6f649b3 · 6f649b3
1 parent 601fbc5
commit 6f649b3
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/Calibration/TkAlCaRecoProducers/plugins/TrackDistanceValueMapProducer.cc b/Calibration/TkAlCaRecoProducers/plugins/TrackDistanceValueMapProducer.cc
@@ -120,7 +120,9 @@ void TrackDistanceValueMapProducer::produce(edm::StreamID streamID,
 
     // just copy the first nth
     std::vector<float> reduced_vdR2;
-    std::copy(v_dR2.begin(), v_dR2.begin() + nthClosestTrack_, std::back_inserter(reduced_vdR2));
+    if (v_dR2.size() > 0){
+      std::copy(v_dR2.begin(), v_dR2.begin() + nthClosestTrack_, std::back_inserter(reduced_vdR2));
+    }
     v2_dR2.push_back(reduced_vdR2);
   }