TH1F - Multiple Root Files

Hello root talkers,

I am relatively new to the ROOT platform and I am encountering a problem when trying to use TH1F class to display histograms from different root files.

I am unsure if what I am trying to do is possible however I am trying to plot 4 histograms on one canvas with each canvas pertaining to a different root file.

All root files contain the same tree and leaves. Each of the 4 TChains differ solely by a measurement length that was changed in the sim to prdocue the root files.

I am not producing any errors from root however only one histogram is plotted.

(Basically, I am trying to plot the flux of a particle through a number of planes. Each of the 4 jobs contain the same root file with the same variable/planes however the (x,y,z) coordinates are changed for each job. I am curious on how the flux of particles through each plane changes as the distance increases. I thought a 2x2 canvas would display the fluxes for each job.)

I am running version 5.14 on Scientific Linux 4.7. My file is listed below.

Thank you for the help

// Read in job101

    TChain files101 ("h50");

    for (Int_t ifile101 = 1; ifile101 <= 99; ifile101++)

    {

         files101.Add(Form("/amd/lnxdata304/nfs/data34/boone/fordd/GNUMI_MUONS/

batch/job1000/batch_testplanes_%i.root", ifile101));         

    }

// Read in job201

    TChain files201 ("h50");

    for (Int_t ifile201 = 102; ifile201 <= 200; ifile201++)

    {

         files201.Add(Form("/amd/lnxdata304/nfs/data34/boone/fordd/GNUMI_MUONS/

batch/job1000/batch_testplanes_%i.root", ifile201));         

    }

// Read in job301

    TChain files301 ("h50");

    for (Int_t ifile301 = 202; ifile301 <= 299; ifile301++)

    {

         files301.Add(Form("/amd/lnxdata304/nfs/data34/boone/fordd/GNUMI_MUONS/

batch/job1000/batch_testplanes_%i.root", ifile301));         

    }

// Read in job501

    TChain files501 ("h50");

    for (Int_t ifile501 = 400; ifile501 <= 499; ifile501++)

    {

         files501.Add(Form("/amd/lnxdata304/nfs/data34/boone/fordd/GNUMI_MUONS/

batch/job1000/batch_testplanes_%i.root", ifile501));         

    }

// Histograms for particles going through planes for each job

    TH1F *muon_plane_job101 = new TH1F("muon_plane_job101","",100,0,10.);

    TH1F *muon_plane_job201 = new TH1F("muon_plane_job201","",100,0,10.);

    TH1F *muon_plane_job301 = new TH1F("muon_plane_job301","",100,0,10.);

    TH1F *muon_plane_job501 = new TH1F("muon_plane_job501","",100,0,10.);

// Plotting histograms for each job

    files101.Draw("plane >> muon_plane_job101", "(type == 5) || (type == 6)");

    files201.Draw("plane >> muon_plane_job201", "(type == 5) || (type == 6)");

    files301.Draw("plane >> muon_plane_job301", "(type == 5) || (type == 6)");

    files501.Draw("plane >> muon_plane_job501", "(type == 5) || (type == 6)");

// Create new canvas and divide into 4 pads

    TCanvas *c1 = new TCanvas("c1", "Distribution of Muons Through Each Plane",

1100,700);

    c1->Divide(2,2);

// 1st Pad

    c1->cd(1);

    muon_plane_job101->Draw();

// 2nd Pad

    c1->cd(1);

    muon_plane_job501->Draw();

// 3rd Pad

    c1->cd(1);

    muon_plane_job301->Draw();

// 4th Pad

    c1->cd(1);

    muon_plane_job201->Draw();      Received on Tue Apr 27 2010 - 15:14:00 CEST