Plotting several variables by using array

dsahoo · April 18, 2018, 5:21am

Dear Experts,

I want to plot several variables from tree by using array. Here, I am trying to plot two variables from a tree (Bmass, Mumumass) by using array. I am attaching my macro here. I have defined two arrays : one for variables(Bmass, Mumumass) and another for cuts(selbm0, selbm1,…etc). It is giving segmentation violation error. I also want to define different histograms for these two variables. Could you please tell me how to get rid of the error?

Thanks,
Deepakmultivar.cc (1.7 KB)

couet · April 18, 2018, 7:25am

Your code has several mistakes which I tried to fix in the following code. I used clout instead of TTree:Draw because I do not have your data file. but putting back theDraw` command should be fine.

{

   const int n = 2;
   const int m = 7;

   string varmass[n] = {"Bmass","Mumumass"};
   string varsel [m] = {"selbm0","selbm1","selbm2","selbm3","selbm4","selbm5","selbm6"};

   for (int i = 0; i<n; i++){
      for (int j = 0; j<m; j++){
         cout << Form("%s",varsel[j].c_str()) <<endl;
      }
   }
}

dsahoo · April 18, 2018, 10:10am

Hi Couet,

I tried, but it is giving error. I am attaching the snapshot of error.

Thanks,
Deepak

dsahoo · April 18, 2018, 2:32pm

Hi,

It is showing segmentation violation.

Thanks,
Deepakmultivar.cc (2.2 KB)

couet · April 18, 2018, 2:41pm

{
   const int n = 2;
   const int m = 7;

   TCut Q[7];
   Q[0]= "Q2> 1.0 && Q2 < 4.30";
   Q[1]= "Q2> 4.30 && Q2 < 8.68";
   Q[2]= "Q2> 8.68 && Q2 < 10.09";
   Q[3]= "Q2> 10.09 && Q2 < 12.86";
   Q[4]= "Q2> 12.86 && Q2 < 14.18";
   Q[5]= "Q2> 14.18 && Q2 < 16.0";
   Q[6]= "Q2> 16.0 && Q2 < 19.0";

   for (int i = 0; i<n; i++){
    for (int j = 0; j<7; j++){
      tr->Draw("Q2",Q[j]);
    }
   }
}

dsahoo · April 18, 2018, 2:54pm

Hi,

Still, it is giving segmentation violation error.

Thanks,
Deepak

couet · April 18, 2018, 2:56pm

can you post you macro and a data file so i can run the real macro … I am just guessing right now as I do not have your data…

dsahoo · April 18, 2018, 3:02pm

Here is the macro and data file.

Thanks,
Deepakmultivar.cc (2.2 KB)
sel_BsToPhiMuMu_2016H_cut1_data_s0.root (844.4 KB)

couet · April 18, 2018, 3:05pm

This one is working for me:

{
  gStyle->SetOptStat("emr");

  TChain *ch = new TChain("tree");
  ch->Add("sel_BsToPhiMuMu_2016H_cut1_data_s0.root");

  TTree *tr = ch;

  double Bmass= 0;
  double Mumumass = 0;
  double CosThetaK = 0;
  double CosThetaL = 0;


  tr->SetBranchStatus("*",0);
  tr->SetBranchStatus("Bmass"         , 1);
  tr->SetBranchStatus("Q2"         , 1);
  tr->SetBranchStatus("Mumumass"         , 1);
  tr->SetBranchStatus("Mumumasserr"         , 1);
  tr->SetBranchStatus("Triggers"         , 1);
  tr->SetBranchStatus("CosThetaL"      ,1);
  tr->SetBranchStatus("CosThetaL"    ,1);


  const int n = 2;
  const int m = 7;

  TCut Q[7];
   Q[0]= "Q2> 1.0 && Q2 < 4.30";
   Q[1]= "Q2> 4.30 && Q2 < 8.68";
   Q[2]= "Q2> 8.68 && Q2 < 10.09";
   Q[3]= "Q2> 10.09 && Q2 < 12.86";
   Q[4]= "Q2> 12.86 && Q2 < 14.18";
   Q[5]= "Q2> 14.18 && Q2 < 16.0";
   Q[6]= "Q2> 16.0 && Q2 < 19.0";

  string varmass[n] = {"Bmass","Mumumass"};
  //  string varsel [m] = {"selbm0","selbm1","selbm2","selbm3","selbm4","selbm5","selbm6"};

  for (int i = 0; i<n; i++){
    for (int j = 0; j<7; j++){
      tr->Draw("Q2",Q[j]);
    }
  }
}

Wile_E_Coyote · April 19, 2018, 6:28am

{
  gStyle->SetOptStat("emr");
  
  TChain *tr = new TChain("tree");
  tr->Add("sel_BsToPhiMuMu_2016H_cut1_data_s0.root");
  // tr->Print();
  
  tr->SetBranchStatus("*", 0);
  tr->SetBranchStatus("Bmass", 1);
  tr->SetBranchStatus("Mumumass", 1);
  tr->SetBranchStatus("Phimass", 1);
  tr->SetBranchStatus("Q2", 1);
  
  const char *varmass[] = {"Bmass", "Mumumass", "Phimass"};
  Int_t n = sizeof(varmass) / sizeof(char*);
  
  TCut Q[] = {"Q2 > 1.0 && Q2 < 4.30",
              "Q2 > 4.30 && Q2 < 8.68",
              "Q2 > 8.68 && Q2 < 10.09",
              "Q2 > 10.09 && Q2 < 12.86",
              "Q2 > 12.86 && Q2 < 14.18",
              "Q2 > 14.18 && Q2 < 16.0",
              "Q2 > 16.0 && Q2 < 19.0"}
  Int_t m = sizeof(Q) / sizeof(TCut);
  
  TCanvas *c = new TCanvas("c", "c");
  c->Divide(m, n);
  // c->DivideSquare(n * m);
  
  Int_t p = 1;
  for (Int_t i = 0; i < n; i++) {
    for (Int_t j = 0; j < m; j++) {
      c->cd(p++);
      tr->Draw(varmass[i], Q[j]);
    }
  }
  c->cd(0);
}

dsahoo · April 23, 2018, 8:56am

Hi Cooyote,

Many thanks. Could you please tell me “Int_t n = sizeof(varmass) / sizeof(char*);”, what it means?

Thanks,
Deepak

couet · April 23, 2018, 9:03am

To compute automatically n and m

dsahoo · April 23, 2018, 9:09am

Hi couet,

If I want to plot each distribution in one canvas, how ?

Thanks,
Deepak

couet · April 23, 2018, 9:17am

Open a new canvas for each plot.

dsahoo · April 25, 2018, 5:06am

Hi Couet,

I want to set ranges for Bmass, Mumumass and Phimass histograms. Could you please tell me how to do it?

Thanks,
Deepak

Wile_E_Coyote · April 25, 2018, 6:28am

Try something like:

  // ...
  TCut Qmass[] = {"Bmass > 0. && Bmass < 1.",
                  "Mumumass > 0. && Mumumass < 1.",
                  "Phimass > 0. && Phimass < 1."}
  // ...
      tr->Draw(varmass[i], Qmass[i] && Q[j]);

dsahoo · April 25, 2018, 6:31am

Hi Wile,

I don’t want to apply mass cut. I want to define histogram for each variable(Bmass, Mumumass, Phimass) and set ranges of histograms.

Thanks,
Deepak

Wile_E_Coyote · April 25, 2018, 6:36am

Try: tr->Project("SomeHistoName", varmass[i], Q[j]);
See: TTree::Project

dsahoo · April 25, 2018, 7:02am

Hi Wile,

How to define histogram for all the three variables?

Thanks,
Deepak

Wile_E_Coyote · April 25, 2018, 7:07am

You need to create as many histograms as you need (with different “HistoNames”) and then use their names in the loop.