Histogram multiply and division

Hello,

I need to calculate the efficiency using bin by bin (2D).I used following equation and code it as follows.

 Efficiency=(h2_pim_4fold_exc)/(h2_pim_3fold_exc- normalized bgnd);
  normlaized_bgnd= (h2_pim_3fold_bgnd/h2_pim_4fold_bgnd_notexc)* h2_pim_4fold_exc_notexc;

I am really disappointed the answer I got.Is something wrong with my code(sorry for the confused names for the histograms)

{
    
    //f_bgd= (Integrate 3-fold)/(Integrated 4-fold !Exc) in bgnd region
    TH2F *f_bgnd=(TH2F*)h2_pim_3fold_bgnd->Clone("f_bgnd");
    f_bgnd->Divide(h2_pim_4fold_bgnd_notExc);
    
//     normalized bgnd = f_bgd * (4-fold !Exc integrated over "exclusive" window of missing pi- M2)
    TH2F* Normalized_bgnd=(TH2F*) f_bgnd->Clone("Normalized_bgnd");
    Normalized_bgnd->Multiply(h2_pim_4fold_exc_notExc);
    
 //   (h2_pim_3fold_exc- normalized bgnd)
    TH2F* Neg_Normalized_bgnd= (TH2F*) Normalized_bgnd->Clone("Neg_Normalized_bgnd");
    Neg_Normalized_bgnd->Scale(-1);
    h2_pim_3fold_exc->Add(Neg_Normalized_bgnd);
    
    // Efficiency=(h2_pim_4fold_exc)/(h2_pim_3fold_exc- normalized bgnd);
    TH2F * Efficiency= (TH2F*) h2_pim_4fold_exc->Clone("Efficiency");
     Efficiency->Divide(h2_pim_4fold_exc,h2_pim_3fold_exc);
    
    Efficiency->SetMarkerSize(1.5);
    Efficiency->Draw("text30");
    
    }

Any hint would be greatly appreciated.

Thanks

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The code seems good to me and it seems to follow the operations you have shown above.
What is wrong with the result you have ?

Hello moneto,

The following two ways gave me different answers.Which one is correct?

TH2F * Normalized_bgnd=(TH2F*)h2_pim_3fold_exc->Clone("Normalized_bgnd");
        Normalized_bgnd->Divide(h2_pim_4fold_bgnd_notExc);
        Normalized_bgnd->Multiply(h2_pim_4fold_exc_notExc);
//f_bgd= (Integrate 3-fold)/(Integrated 4-fold !Exc) in bgnd region
    TH2F *f_bgnd=(TH2F*)h2_pim_3fold_bgnd->Clone("f_bgnd");
    f_bgnd->Divide(h2_pim_4fold_bgnd_notExc);
    
//     normalized bgnd = f_bgd * (4-fold !Exc integrated over "exclusive" window of missing pi- M2)
    TH2F* Normalized_bgnd=(TH2F*) f_bgnd->Clone("Normalized_bgnd");
    Normalized_bgnd->Multiply(h2_pim_4fold_exc_notExc);

Thanks

Hello,

Can someone help me to do Efficiency calulation using TEfficiency?

{
    
    //f_bgd= (Integrate 3-fold)/(Integrated 4-fold !Exc) in bgnd region
    TH2F *f_bgnd=(TH2F*)h2_pim_3fold_bgnd->Clone("f_bgnd");
    f_bgnd->Divide(h2_pim_4fold_bgnd_notExc);
    
//     normalized bgnd = f_bgd * (4-fold !Exc integrated over "exclusive" window of missing pi- M2)
    TH2F* Normalized_bgnd=(TH2F*) f_bgnd->Clone("Normalized_bgnd");
    Normalized_bgnd->Multiply(h2_pim_4fold_exc_notExc);
    
 //   (h2_pim_3fold_exc- normalized bgnd)
    TH2F* Neg_Normalized_bgnd= (TH2F*) Normalized_bgnd->Clone("Neg_Normalized_bgnd");
    Neg_Normalized_bgnd->Scale(-1);
    h2_pim_3fold_exc->Add(Neg_Normalized_bgnd);
    
    // Efficiency=(h2_pim_4fold_exc)/(h2_pim_3fold_exc- normalized bgnd);
    TH2F * Efficiency= (TH2F*) h2_pim_4fold_exc->Clone("Efficiency");
     Efficiency->Divide(h2_pim_4fold_exc,h2_pim_3fold_exc);
    
    Efficiency->SetMarkerSize(1.5);
    Efficiency->Draw("text30");
    
    }

Thanks
Dil

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