How to add text in graph

Newbie
1

Hi !
I am working on a code to add text to my graph but it is not able to write more than one line in the graph or canvas.
efficiency_R.C (1.9 KB) rad_9.txt (340 Bytes)

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

2

TPaveText

3

@Wile_E_Coyote
Actually I used TpaveText in my code.
Still I am not able to write more than one line in canvas.

4

Read the reference page; you need to provide the coordinates of the box when you create a TPaveText.

5 
#include "TFile.h"
#include "TGraphErrors.h"
#include "TF1.h"

Double_t Fit1(Double_t *x, Double_t *par)
{
        Double_t arg1     = TMath::Log(0.01*x[0]);          // in keV
        Double_t arg2     = TMath::Log(0.001*x[0]);          // in keV

            Double_t fit_val = TMath::Exp(TMath::Power((TMath::Power((par[0]+par[1]*arg1+par[2]*arg1*arg1),(-1.0*par[3]))+TMath::Power((par[4]+par[5]*arg2+par[6]*arg2*arg2),(-1.0*par[3]))),(-1.0*1/par[3])))/1000.;
        return fit_val;
}

void efficiency_R() {
   TGraphErrors *g = new TGraphErrors("rad_9.txt", "%lg %lg %lg");
   TF1 *RT = new TF1("RT",Fit1,100.,1500.,7.);

   //rad 6,7
   RT->SetParameter(0,16.);
   RT->SetParameter(1,7.5);
   RT->FixParameter(2,0.);
   RT->FixParameter(3,15.);
   RT->SetParameter(4,15.);
   RT->SetParameter(5,-0.78);
   RT->SetParameter(6,.015);

   RT->Draw("L");
   g->SetMaximum(15000.);//along Y
   g->Fit("RT","IER");
   g->SetMarkerStyle(3);
   g->Draw("AP");
   g->SetTitle("Efficiency Vs Energy(keV);Energy;Efficiency");
   gStyle->SetOptFit(111);  //showing the parameters on graph

   TPaveText *pt = new TPaveText(77.6016,12857.83,971.9464,14578.31);
   pt->SetBorderSize(0);
   pt->SetFillColor(0);
   pt->SetFillStyle(0);
   pt->AddText("Exp{[(P0+P1*X+P2*X*X)**(-P3)+(P4+P5*Y+P6*Y*Y)**(-P3)]**(-1/P3)}");
   pt->AddText("WITH     X = LOG (X/100)     &     Y = LOG (X/1000)");
   pt->Draw();

   double par[7];
   RT->GetChisquare();
   RT->GetParameters(par);
   double a = 700.0, y;
   y = RT->Eval(a);
   cout << "y = "<<y<<endl;
}
6

@couet
can I get directly the value of chi square written in the stat box? If yes, then what I have to use?

7 
RT->GetChisquare();
8

@couet
I used this but I am talking about the stat box in the canvas.

9

gStyle->SetOptFit(100);

@couet Maybe you could copy (“replicate”) the very first “Note” from TStyle::SetOptStat to TStyle::SetOptFit.

10

@robertfroast sorry I understood the opposite. see Wile answer
@Wile_E_Coyote yes it makes sense.

11

PR ready: https://github.com/root-project/root/pull/5602

12

@couet

 ///  - never call SetOptFit(0111) but call SetOptFit(111) or SetOptFit(10111), 0111 will

and then also maybe correct:

 ///  - never call SetOptStat(000000111) but call SetOptStat(111) or SetOptStat(1000000111), 000000111 will
13

Yes @bellenot saw it also (PR reviewer). Thanks !