RE: Mixed events from a TChain

Hi Rene,

On Thu, 2005-01-06 at 08:08 +0100, Rene Brun wrote:
> Christian,
>
> See example in tutorial copytree3.C

This example _copies_ the tree. That's _not_ what I want to do. I want to loop over the entries, and for each iteration read in the current entry, as well as some previous entry:

	Int_t delayed = 2;
	TTree* tree  = static_cast<TTree*>(file->Get("T"));
	TTree* delay = new MixTree(tree); 
	tree->SetBranchAddress("data", &data); 
	delay->SetBranchAddress("data", &previous); 

	Int_t n = tree->GetEntries();
	for (Int_t i = 0; i < n; i++) {
	   Int_t read = tree->GetEntry(i);
	   if (read < 0) {	
	     Error("...", "Error reading from tree");
	     break;
	   }
	   if  (read == 0) break;
	   
	   if (i <= delayed) break;

	   read = delay->GetEntry(i-delayed);
	   if (read < 0) { 
	     Error("...", "Error reading old entry");
	     break; 
	   } 
	
	   // Do mixed event analysis on the data in `data' 
	   // and `previous'
	}

This is not the same as copying the tree, and using TTree::CloneTree is a gross misuse that member function (not to say ineffcient). Please also refer to my previous email, and the attachments in it.

Thank you for your help anyway.

Yours,

-- 
 ___  |  Christian Holm Christensen 
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