Issue when projecting a TH3

[martis]

Hello,

I encountered an issue while projecting a TH3 into a TH1. It basically works, but when I use the “e” option the number of entries changes.

This is the straight output:
root [8] h1_3DPtPosMu->GetEntries()
(double) 527930.000000
root [9] h1_3DPtPosMu->ProjectionZ(“hpos_0”,-1,-1,-1,-1)->GetEntries()
(double) 527930.000000
root [10] h1_3DPtPosMu->ProjectionZ(“hpos_e”,-1,-1,-1,-1)->GetEntries()
(double) 527930.000000

I would expect the “e” option has no effect on the number of entries in the projected.

Cheers
Salva

[martis]

Apologize for the spam. The screen capture I sent was wrong. It was not showing the effect of the “e” option. Please read the one here below.

root [1] h1_3DPtPosMu->GetEntries()
(double) 527930.000000
root [2] h1_3DPtPosMu->ProjectionZ(“hpos_0”,-1,-1,-1,-1)->GetEntries()
(double) 527930.000000
root [3] h1_3DPtPosMu->ProjectionZ(“hpos_e”,-1,-1,-1,-1,“e”)->GetEntries()
(double) 527566.000000

Cheers
Salva

[couet]

I guess @moneta can help you

[moneta]

Hi,

Is the histogram weighted ? In this case the effective entries will be computed and by using option “e” the effective entries will be different

Lorenzo

[martis]

Hi

yes, the histogram is weighted, but in this test all weights sould

be 1.

However, now I am confused about what the "e" option does.

Cheers

Salva