{
//
// An example to draw various variables in the SVAC ntuple!
// Original author: Chen, Xin (xchen@slac.stanford.edu)
// Additionas and comments by anders (borgland@slac.stanford.edu) 
//

//
// To run this macro, do: root drawSvac.C
// Or if you are already in ROOT: .x drawSvac.C
//


gROOT->Reset();

//
// Name of the SVAC ntuple file you want to look at:
//
TFile* f1 = new TFile("/nfs/farm/g/glast/u01/svac_workshop/Workshop-3/Data/GlastRelease_v6r2p1-AdditionalCAL/Run-140001338/140001338_svac.root");

//
// 'Output' is the name of the Root tree in the SVAC ntuple and 
// automatically becomes a pointer to that tree.
// Can also explicitly do: 
//TTree *Output = (TTree*) f1.Get("Output");
 

// More details about the SVAC ntuple variables are found 
// in the SVAC ntuple decsription available from the main 
// Instrument Analysis page. 


//
// This time we will put four plots on the same canvas:
//

// Define the canvas:
TCanvas* c1 = new TCanvas;
// Divide it into 4:
c1->Divide(2,2);
//
gPad->SetBorderMode(0);
gPad->SetFillColor(10);



//
// Plot the number of reconstructed tracks:
//
// Go to the upper left corner of the canvas:
c1->cd(1);
// fill the plot with red:
Output->SetFillColor(2);
// Plot:
Output->Draw("TkrNumTracks");



//
// Plot maximal energy in a CAL crystal:
//
// Go to the upper right corner of the canvas:
c1->cd(2);
Output->SetFillColor(2);
// Want log scale for this:
gPad->SetLogy();
// Plot the maximum energy when it's greater than 0: 
// Cuts are added in quotes after the first comma.
Output->Draw("CalMaxEne","CalMaxEne>0");



//
// Plot the energy in each crystal: 
// Note that this is an array. Root will here automatically 
// loop over all the entries and plot each separately.
// Here we limit ourselves to the first 100 events!
//
// Go to the lower left corner of the canvas:
c1->cd(3);
Output->SetFillColor(2);
// Want log scale for this:
gPad->SetLogy();
// Plot the energy in each crystal when there is energy in the CAL 
// for the first 100 events: 
Output->Draw("CalXtalEne","CalMaxEne>0","","100");



//
// Plot the number of strips per layer and view: 
// This is an array and Root will loop over all the entries.
//
// Go to the lower right corner of the canvas:
c1->cd(4);
Output->SetFillColor(2);
// Want log scale for this:
gPad->SetLogy();
// Plot all the elements of the array for the first 100 events:
Output->Draw("TkrNumStrips","","","100");

}