Fix: fix index access

Author: ariedel-cern

PWGCF/Femto/Core/collisionBuilder.h

@@ -82,7 +82,7 @@ struct ConfCollisionBits : o2::framework::ConfigurableGroup {
   o2::framework::Configurable<std::vector<float>> sphericityMax{"sphericityMax", {}, "Maximum sphericity"};
   o2::framework::Configurable<std::vector<std::string>> triggers{"triggers", {}, "List of all triggers to be used"};
   o2::framework::Configurable<datatypes::QvecDetectorType> qvecDetector{"qvecDetector", 0, "Detector used to estimate the Q-vector: 0 -> FT0C, 1 -> FT0A"};
-  o2::framework::Configurable<datatypes::QvecHarmonicType> qvecHarmonic{"qvecHarmonic", 2, "Harmonic n of the Q-vector and event plane angle Psi_n: 1 -> direct, 2 -> elliptic, 3 -> triangular"};
+  o2::framework::Configurable<datatypes::QvecHarmonicType> qvecHarmonic{"qvecHarmonic", 2, "Harmonic n of the Q-vector and event plane angle Psi_n: 2 -> elliptic, 3 -> triangular"};
 };
 
 struct ConfCcdb : o2::framework::ConfigurableGroup {
@@ -370,12 +370,16 @@ class CollisionSelection : public baseselection::BaseSelection<float, o2::analys
   void setEventPlane(T const& col)
   {
     auto harmonic = static_cast<float>(mQvecHarmonic);
+    int index = static_cast<int>(mQvecHarmonic) - 2; // get index in the qvector vector
+    if (index >= 2) {
+      LOG(fatal) << "At the moment harmonics up to 3 are supported!";
+    }
     switch (mQvecDetector) {
       case modes::QvecDetector::kFT0C:
-        mEventPlane = RecoDecay::constrainAngle((std::atan2(col.qvecFT0CImVec()[0], col.qvecFT0CReVec()[0])) / harmonic, 0, harmonic); // constrain between 0 and 2pi/harmonic
+        mEventPlane = RecoDecay::constrainAngle((std::atan2(col.qvecFT0CImVec()[index], col.qvecFT0CReVec()[index])) / harmonic, 0, harmonic); // constrain between 0 and 2pi/harmonic
         break;
       case modes::QvecDetector::kFT0A:
-        mEventPlane = RecoDecay::constrainAngle((std::atan2(col.qvecFT0AImVec()[0], col.qvecFT0AReVec()[0])) / harmonic, 0, harmonic); // constrain between 0 and 2pi/harmonic
+        mEventPlane = RecoDecay::constrainAngle((std::atan2(col.qvecFT0AImVec()[index], col.qvecFT0AReVec()[index])) / harmonic, 0, harmonic); // constrain between 0 and 2pi/harmonic
         break;
     }
   }

PWGCF/Femto/Core/modes.h

@@ -184,7 +184,6 @@ enum class QvecDetector : o2::analysis::femto::datatypes::QvecDetectorType {
 };
 
 enum class QvecHarmonic : o2::analysis::femto::datatypes::QvecHarmonicType {
-  kN1 = 1,
   kN2 = 2,
   kN3 = 3
 };