I am trying to fill branches in a TTree at different times and with a different number of entries. I will state up front that my knowledge of root is very, very minimal. When I run the code below as a test, I get a large root file that indicates the data is actually being stored. However, I cannot see a histogram of the data in the object browser when I click on a leaf.
So my questions are:
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Am I filling the branches correctly? Is it okay to create and fill branches at different times and with different numbers of entries?
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Is there something else I need to be doing to fill these branches individually since the information in the tree isn’t behaving like it typically does (i.e. no histogram)?
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If I’m doing things correctly, how can I generate a histogram of the data when looking at the root tree in the object browser (or in my C++ program if that is easier to do)?
Thank you
–John
// make TFile and TTree
TFile f1("tester.root","RECREATE");
TTree t1("t1","Tree mmmm");
// first branch
Int_t dog;
TBranch* b1 = t1.Branch("dog",&dog,"I");
//second branch
Double_t cat;
TBranch* b2 = t1.Branch("cat",&cat,"D");
// fill the first branch a bunch of times
for(int i = 0; i < 1E7; ++i)
{
++dog;
b1->Fill();
}
// fill the second branch once later
b2->Fill();
// write the file.
f1.Write();