swh:1:snp:af87cd67498ef4fe47c76ed3e7caffe5b61facaf
Tip revision: 5e62eeb9f036ac62a3a00f7daa74c13aaa9e4123 authored by Rene Brun on 12 March 2008, 07:49:22 UTC
Tagging dev release 5.19/02
Tagging dev release 5.19/02
Tip revision: 5e62eeb
dirs.C
void dirs() {
// .........................macro dirs.C............................
// This macro illustrates how to create a hierarchy of directories
// in a Root file.
// 10 directories called plane0, plane1, plane9 are created.
// Each plane directory contains 200 histograms.
//
// Run this macro (Note that the macro delete the TFile object at the end!)
// Connect the file again in read mode:
// Root > TFile *top = new TFile("top.root");
// The hierarchy can be browsed by the Root browser as shown below
// Root > TBrowser b;
// click on the left pane on one of the plane directories.
// this shows the list of all histograms in this directory.
// Double click on one histogram to draw it (left mouse button).
// Select different options with the right mouse button.
//
// You can see the begin_html <a href="gif/dirs.gif" >picture of the browser </a> end_html
//
// Instead of using the browser, you can also do:
// Root > tof->cd();
// Root > plane3->cd();
// Root > h3_90N->Draw();
//Author: Rene Brun
// create a new Root file
TFile *top = new TFile("top.root","recreate");
// create a subdirectory "tof" in this file
TDirectory *cdtof = top->mkdir("tof");
cdtof->cd(); // make the "tof" directory the current directory
// create a new subdirectory for each plane
const Int_t nplanes = 10;
const Int_t ncounters = 100;
char dirname[50];
char hname[20];
char htitle[80];
Int_t i,j,k;
TDirectory *cdplane[nplanes];
TH1F *hn[nplanes][ncounters];
TH1F *hs[nplanes][ncounters];
for (i=0;i<nplanes;i++) {
sprintf(dirname,"plane%d",i);
cdplane[i] = cdtof->mkdir(dirname);
cdplane[i]->cd();
// create counter histograms
for (j=0;j<ncounters;j++) {
sprintf(hname,"h%d_%dN",i,j);
sprintf(htitle,"hist for counter:%d in plane:%d North",j,i);
hn[i][j] = new TH1F(hname,htitle,100,0,100);
sprintf(hname,"h%d_%dS",i,j);
sprintf(htitle,"hist for counter:%d in plane:%d South",j,i);
hs[i][j] = new TH1F(hname,htitle,100,0,100);
}
cdtof->cd(); // change current directory to top
}
// .. fill histograms
TRandom r;
for (i=0;i<nplanes;i++) {
cdplane[i]->cd();
for (j=0;j<ncounters;j++) {
for (k=0;k<100;k++) {
hn[i][j]->Fill(100*r.Rndm(),i+j);
hs[i][j]->Fill(100*r.Rndm(),i+j+k);
}
}
}
// save histogram hierarchy in the file
top->Write();
delete top;
}