ROOT Version: 6.18/04
Platform: f30
Compiler: 9.2.1 20190827
Dear co-rooters,
I am trying to plot histograms from a root file on the same canvas. The histograms should have a random colour, using TRandom
, however I can only draw them with one color. I guess I should somehow change the seed, but I have no idea how to do it. Any idea?
My code is the following
void plot_histos(TString filename_in, TString histo_name, TString filename_out){
TFile *fin = new TFile(filename_in, "OPEN");
TCanvas *c = new TCanvas();
//string h_name = filename_in;
for (int i=1; i<11; ++i){
//TH1F *h = (TH1F*) fin->Get(histo_name);
TH1F *h = (TH1F*) fin->Get(TString::Format("%s_%03i", histo_name.Data(), i) );
TRandom *r = new TRandom();
int color = (int) ((113-51)*r->Rndm()+51);
h->SetLineColor(color);
h->Draw("histo same");
}
}
An the result that I get is this
Any idea on how to plot in different and random colours?
Thanks in advance!
P.S.: I am attaching a root file with the histograms
background_2205_h58_dummy_pi_adc.root (28.4 KB)