How can i draw scatter plot?

HyungJoe_Kwon · June 20, 2021, 2:05pm

Hi experts!
I’m root beginner.
I try to draw crystal1:crystal2 scatter plot. However, it comes out as undeclared identifier ‘tree’ as shown in the picture below. What is the problem?

and this is the data structure. Branches are numbered from crystal1 to crystal8.

Please read tips for efficient and successful posting and posting code

ROOT Version: Not Provided
Platform: Not Provided
Compiler: Not Provided

Wile_E_Coyote · June 20, 2021, 2:53pm

// TFile *f = TFile::Open("mrgd_M001506.root.000");
// TTree *ntp; f->GetObject("ntp", ntp);
ntp->Draw("some_leaf : other_leaf");

HyungJoe_Kwon · June 20, 2021, 6:58pm

Thanks for reply!
What is ntp?
And actually I want to draw a scatter plot of the coincident events of crystal 2_energy and crystal 1_energyD,crystal3_energyD,crystal4_energyD,crystal6_energyD,crystal7_energyD.
In other words, the x-axis is crystal 2_energy , and the y-axis is crystal 1, 3, 6, 7_energyD.
What should i do?

Wile_E_Coyote · June 20, 2021, 7:12pm

The name of your tree is “ntp”.
Attach the output of: ntp->Print();

HyungJoe_Kwon · June 20, 2021, 10:42pm

There are so many branches, can I just pick one and show it? For crystal 1

*Br 12 :crystal1 : nc/I:t0/F:t1/F:rqc/F:rqcp/F:rqcn/F:qtail/F:qc/F:qc1/F: *

    | qc1_5/F:qc2/F:qc3/F:qc4/F:qc5/F:qc50/F:qc50_100/F:qc100_200/F:   *

    | qc200_400/F:qc400_1000/F:mt/F:x1/F:x2/F:tzero/F:nmt30/F:nmt300/F:*

    | nmt500/F:nmt1000/F:nmt1500/F:nmt2000/F:nq30/F:nq300/F:nq500/F:   *

    | nq1000/F:nq1500/F:nq2000/F:nx1/F:nx2/F:nx2_80/F:nx2_120/F:       *

    | cr_50/F:cr_100/F:cr_150/F:energy/F:energyD                       *

*Entries : 133495 : Total Size= 23504480 bytes File Size = 1432798 *
*Baskets : 59 : Basket Size= 6665216 bytes Compression= 16.40 *
…

Wile_E_Coyote · June 21, 2021, 6:16am

Try maybe: ntp->Draw("crystal1.energyD : crystal2.energy");

HyungJoe_Kwon · June 21, 2021, 9:42am

Thank you for reply !
So can i draw crystal1.energyD :crystal2.energy, crystal1.energyD :crystal3.energy, crystal1.energyD :crystal4.energy in one plot? I wanna see coincident event between crystal 1 and other crystals.

couet · June 21, 2021, 10:18am

That will produce 3 scatter plots. If you what to have these 4 variable in one single plot you can do:

ntp->Draw("crystal1.energyD:crystal2.energy:crystal3.energy:crystal4.energy");

That will produce a 3D scatter for 3 variables and the 4th one will be map on the current colormap.

Wile_E_Coyote · June 21, 2021, 10:20am

{
  // TFile *f = TFile::Open("mrgd_M001506.root.000");
  // TTree *ntp; f->GetObject("ntp", ntp);
  TCanvas *c = new TCanvas("c", "c", 900, 300);
  c->Divide(3, 1);
  c->cd(1);
  ntp->Draw("crystal1.energyD : crystal2.energy");
  c->cd(2);
  ntp->Draw("crystal1.energyD : crystal3.energy");
  c->cd(3);
  ntp->Draw("crystal1.energyD : crystal4.energy");
  c->cd(0);
}

HyungJoe_Kwon · June 23, 2021, 8:44am

Thanks for reply. But i want to overlap it one spectrum. With out dividing the canvas.

couet · June 23, 2021, 9:13am

{
  // TFile *f = TFile::Open("mrgd_M001506.root.000");
  // TTree *ntp; f->GetObject("ntp", ntp);
  TCanvas *c = new TCanvas("c", "c", 900, 300);
  c->DrawFrame(x1,y1,x2,y2); // make sure x1,y1,x2,y2 are wide enough
  ntp->Draw("crystal1.energyD : crystal2.energy","","SAME");
  ntp->Draw("crystal1.energyD : crystal3.energy","","SAME");
  ntp->Draw("crystal1.energyD : crystal4.energy","","SAME");
}

Wile_E_Coyote · June 23, 2021, 9:57am

{
  // TFile *f = TFile::Open("mrgd_M001506.root.000");
  // TTree *ntp; f->GetObject("ntp", ntp);
  Double_t xmin = ntp->GetMinimum("crystal1.energy");
  xmin = TMath::Min(xmin, ntp->GetMinimum("crystal2.energy"));
  xmin = TMath::Min(xmin, ntp->GetMinimum("crystal3.energy"));
  xmin = TMath::Min(xmin, ntp->GetMinimum("crystal4.energy"));
  Double_t xmax = ntp->GetMaximum("crystal1.energy");
  xmax = TMath::Max(xmax, ntp->GetMaximum("crystal2.energy"));
  xmax = TMath::Max(xmax, ntp->GetMaximum("crystal3.energy"));
  xmax = TMath::Max(xmax, ntp->GetMaximum("crystal4.energy"));
  Double_t ymin = ntp->GetMinimum("crystal1.energyD");
  Double_t ymax = ntp->GetMaximum("crystal1.energyD");
  gStyle->SetCanvasPreferGL(1); // needed for color transparency
  Double_t alpha = 0.25; // e.g. 0.25 or 0.33 or 0.5
  TCanvas *c = new TCanvas("c", "c");
  c->DrawFrame(xmin, ymin, xmax, ymax,
               "all crystals;crystal*.energy;crystal1.energyD");
  ntp->SetMarkerColorAlpha(kBlack, alpha);
  ntp->Draw("crystal1.energyD : crystal1.energy", "", "same");
  ntp->SetMarkerColorAlpha(kRed, alpha);
  ntp->Draw("crystal1.energyD : crystal2.energy", "", "same");
  ntp->SetMarkerColorAlpha(kGreen, alpha);
  ntp->Draw("crystal1.energyD : crystal3.energy", "", "same");
  ntp->SetMarkerColorAlpha(kBlue, alpha);
  ntp->Draw("crystal1.energyD : crystal4.energy", "", "same");
}

HyungJoe_Kwon · June 24, 2021, 2:54am

I don’t know why you use this code

Double_t xmin = ntp->GetMinimum("crystal1.energy");
  xmin = TMath::Min(xmin, ntp->GetMinimum("crystal2.energy"));
  xmin = TMath::Min(xmin, ntp->GetMinimum("crystal3.energy"));
  xmin = TMath::Min(xmin, ntp->GetMinimum("crystal4.energy"));
  Double_t xmax = ntp->GetMaximum("crystal1.energy");
  xmax = TMath::Max(xmax, ntp->GetMaximum("crystal2.energy"));
  xmax = TMath::Max(xmax, ntp->GetMaximum("crystal3.energy"));
  xmax = TMath::Max(xmax, ntp->GetMaximum("crystal4.energy"));
  Double_t ymin = ntp->GetMinimum("crystal1.energyD");
  Double_t ymax = ntp->GetMaximum("crystal1.energyD");

couet · June 24, 2021, 6:39am

To compute the DrawFrame’s parameters.

HyungJoe_Kwon · June 24, 2021, 8:45am

Is this a necessary process? Can’t we just use the range when drawing on the canvas?

HyungJoe_Kwon · June 24, 2021, 9:08am

I follow the code but it shows
Error in TCanvas::Range: illegal world coordinates range: x1=0.000000, y1=-0.125000, x2
=0.000000, y2=1.125000
Error in TCanvas::RangeAxis: illegal axis coordinates range: xmin=0.000000, ymin=0.0000
00, xmax=0.000000, ymax=1.000000
JIT has not been linked in.

HyungJoe_Kwon · June 24, 2021, 9:11am

{
gROOT->SetStyle(“Plain”);
TChain *ch = new TChain(“ntp”);
char filename[300];
for (int i=1; i<=578; i++){
TString datadir = “/data/COSINE/MRGD/phys/V00-04-04/”;
sprintf(filename,“mrgd_M001544.root.%.3d”,i);
ch->Add(datadir+filename);
}
Double_t xmin = ch->GetMinimum(“crystal2.energyD”);
xmin = TMath::Min(xmin, ch->GetMinimum(“crystal1.energyD”));
xmin = TMath::Min(xmin, ch->GetMinimum(“crystal3.energyD”));
xmin = TMath::Min(xmin, ch->GetMinimum(“crystal4.energyD”));
xmin = TMath::Min(xmin, ch->GetMinimum(“crsytal6.energyD”));
xmin = TMath::Min(xmin, ch->GetMinimum(“crystal7.energyD”));
Double_t xmax = ch->GetMaximum(“crystal2.energyD”);
xmax = TMath::Max(xmax, ch->GetMaximum(“crystal1.energyD”));
xmax = TMath::Max(xmax, ch->GetMaximum(“crystal3.energyD”));
xmax = TMath::Max(xmax, ch->GetMaximum(“crystal4.energyD”));
xmax = TMath::Max(xmax, ch->GetMaximum(“crystal6.energyD”));
xmax = TMath::Max(xmax, ch->GetMaximum(“crystal7.energyD”));
Double_t ymin = ch->GetMinimum(“crystal2.energy”);
Double_t ymax = ch->GetMaximum(“crystal2.energy”);
gStyle->SetCanvasPreferGL(1);
TCanvas *c = new TCanvas(“c”,“c”);
c->DrawFrame(xmin, ymin, xmax, ymax, “Coincident event”);

ch->Draw(“crystal1.energyD:crystal2.energy”,"",“same”);
ch->Draw(“crystal3.energyD:crystal2.energy”,"",“same”);
ch->Draw(“crystal4.energyD:crystal2.energy”,"",“same”);
ch->Draw(“crystal6.energyD:crystal2.energy”,"",“same”);
ch->Draw(“crystal7.energyD:crystal2.energy”,"",“same”);

TFile o(“C2_Coincidentevent_1544.root”,“RECREATE”);
}
This is the code i wrote.

couet · June 24, 2021, 9:13am

What are the values of xmin, ymin, xmax, ymax just before calling DrawFrame ?

HyungJoe_Kwon · June 24, 2021, 9:20am

You mean the values of energy? I couldn’t understand your question.

couet · June 24, 2021, 9:29am

No, I mean check the values you pass to DrawFrame. They seems not correct.
Put the following line just before DrawFrame to check:

printf("xmin = %g, ymin = %g, xmax = %g, ymax = %g",xmin, ymin, xmax, ymax);