Added an additional safety check before eigen-value calculation.

cms-tau-pog · Dec 29, 2020 · 58c99c2 · 58c99c2
1 parent 1426f18
commit 58c99c2
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/RecoEgamma/EgammaTools/src/HGCalShowerShapeHelper.cc b/RecoEgamma/EgammaTools/src/HGCalShowerShapeHelper.cc
@@ -263,6 +263,10 @@ const HGCalShowerShapeHelper::ShowerWidths HGCalShowerShapeHelper::getPCAWidths(
   covMat(0, 2) = covMat(2, 0) = dzdx;
   covMat(1, 2) = covMat(2, 1) = dydz;
 
+  if (!covMat.Sum()) {
+    return ShowerWidths();
+  }
+
   // Get eigen values and vectors
   TVectorD eigVals(3);
   TMatrixD eigVecMat(3, 3);