[solved] How to set style properly?

ROOT
1

I often draw many histogram sets simultaneously, and each needs different style. I encountered problems with changing the style properly. Sometimes the style doesn’t change immediately, but only after drawing one histogram with the old style, and sometimes the style changes also in already drawn histograms.

I wrote a macro that demonstrates my problems:

//test.cc
#include <TCanvas.h>
#include <TMath.h>
#include <TStyle.h>
#include <TH1D.h>

void test() {
	TH1D * h[10];
	TCanvas *c = new TCanvas("c", "c", 800, 600);
	c->Divide(5, 2);
	for(Int_t i = 0; i < 10; ++i) {
		char name[100]; sprintf(name, "h%d", i);
		h[i] = new TH1D(name, name, 10, 0, 1);
		
		gStyle->SetOptStat(TMath::Even(i));
		gStyle->SetTitleH((i+1)/10.);
		c->cd(i+1);
		h[i]->Draw();
	}
	c->SaveAs("c.png");
}

I want the statbox appear on the even histograms (0, 2, 4…), and that the title height changes from 0.1 to 1.0. If I run the macro the title height changes as I wanted, but the statbox is present only in the odd histograms (1, 3, 5…). Another funny thing is that if I comment out the “SetOptStat” line, then all 10 histograms have title height equal 1!

Using DrawClone(), or DrawCopy() instead of Draw() doesn’t help. I also tried using h[i]->UseCurrentStyle(), but then the statbox is never drawn.

What am I doing wrong? :confused:

2

Have you tried : gROOT->ForceStyle(); ?

3

Yes, I have tried it. Actually I’m not sure where should I put it precisely…

Is there somewhere an example of code generating many histograms, each using different style?

4

Style should be used to set global settings, not individual ones like in your macro.
For individual settings you should change the attribute directly on the object you want to modify. Any way your macro seems to work as it should. I the the attached picture.

c.gif796×572 13.6 KB

5

[quote=“couet”]Style should be used to set global settings, not individual ones like in your macro.
For individual settings you should change the attribute directly on the object you want to modify.[/quote]
But I don’t see any method in TH1D to modify (for example) the size of the title… How should I do this?

No it doesn’t. I want the statbox appear on the the even histograms (0, 2, 4, 6, 8 ). On your picture (which look the same as mine) the statbox is on histograms 1, 3, 5, 7. This is why I started to wonder if I write the commands in proper order… but I couldn’t find a combination that would work as I want.

6 
{
   TH1D * h[10];
   TCanvas *c = new TCanvas("c", "c", 800, 600);
   c->Divide(5, 2);
   for(Int_t i = 0; i < 10; ++i) {
      char name[100]; sprintf(name, "h%d", i);
      h[i] = new TH1D(name, name, 10, 0, 1);
      h[i]->SetStats(TMath::Even(i));
      gStyle->SetTitleH((i+1)/10.);
      c->cd(i+1);
      h[i]->Draw();
      gPad->Update();
   }
   c->SaveAs("c.gif");
}
7

This works! Thank you very much :smiley: