TVector2::Phi()

ROOT
1

Dear experts,

The implementation in root.cern.ch/root/html/src/TVector2.cxx.html#66 :

return TMath::Pi()+TMath::ATan2(-fY,-fX);

I wonder why we don’t return TMath::ATan2( fY, fX) directly ?

Thanks,
Jike

2

HI
You are right, one could return directly TMath::ATan2( fY, fX)
Lorenzo

3

Hi Lorenzo,

If so why put such a confusing implementation there …

Cheers,
Jike

[quote=“moneta”]HI
You are right, one could return directly TMath::ATan2( fY, fX)
Lorenzo[/quote]

4

This is very old code and I don’t know who implemented.
I can just say that the new version of Geometry vectors (Math/GenVector/Cartesian2D.h) implements Phi() in the simpler way as you have suggested

Lorenzo

5

Oh, I see. Thanks!

Cheers,
Jike

[quote=“moneta”]This is very old code and I don’t know who implemented.
I can just say that the new version of Geometry vectors (Math/GenVector/Cartesian2D.h) implements Phi() in the simpler way as you have suggested

Lorenzo[/quote]