bugfix in deltaPhi normalisation

jjuracka · jjuracka · commit e0a94a9c2288 · 2026-01-07T10:26:29.000+01:00
diff --git a/PWGUD/Tasks/upcRhoAnalysis.cxx b/PWGUD/Tasks/upcRhoAnalysis.cxx
@@ -674,7 +674,10 @@ struct UpcRhoAnalysis {
   double deltaPhi(const ROOT::Math::PxPyPzMVector& p1, const ROOT::Math::PxPyPzMVector& p2)
   {
     double dPhi = p1.Phi() - p2.Phi();
-    dPhi = std::fmod(dPhi + o2::constants::math::PI, o2::constants::math::TwoPI) - o2::constants::math::PI; // normalize to (-pi, pi)
+    while (dPhi > o2::constants::math::PI)
+      dPhi -= o2::constants::math::TwoPI;
+    while (dPhi < -o2::constants::math::PI)
+      dPhi += o2::constants::math::TwoPI;
     return dPhi;
   }
 

Original file line number	Diff line number	Diff line change
`@@ -674,7 +674,10 @@ struct UpcRhoAnalysis {`
`674`	`674`	`double deltaPhi(const ROOT::Math::PxPyPzMVector& p1, const ROOT::Math::PxPyPzMVector& p2)`
`675`	`675`	`{`
`676`	`676`	`double dPhi = p1.Phi() - p2.Phi();`
`677`		`- dPhi = std::fmod(dPhi + o2::constants::math::PI, o2::constants::math::TwoPI) - o2::constants::math::PI; // normalize to (-pi, pi)`
	`677`	`+ while (dPhi > o2::constants::math::PI)`
	`678`	`+ dPhi -= o2::constants::math::TwoPI;`
	`679`	`+ while (dPhi < -o2::constants::math::PI)`
	`680`	`+ dPhi += o2::constants::math::TwoPI;`
`678`	`681`	`return dPhi;`
`679`	`682`	`}`
`680`	`683`