Merging TTrees from different TDirectorys

[lovell]

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ROOT Version: 6.08/06
Platform, Compiler: x86_64-slc6-gcc62

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Hi,
I’m trying to take two TTrees with the same name, each in a different TDirectory in a file, and merge them. I am having trouble figuring out how to do this, either with TChain or hadd. TChain doesn’t like wildcards like

TChain ch("*/TreeName")
ch.Add("file1.root")
ch.Add("file2.root")
ch.Draw("x")

and using hadd doesn’t work given the different directory names.
How would I achieve this? Apologies if this is duplicated somewhere.

Edit: to clarify, the structure is

1. file.root
   1.1 directory1
   1.1.1 TreeName
   1.2 directory2
   1.2.1 TreeName

Many thanks,
George

[beojan]

You can add the trees to a TList then use TTree::Merge.

[lovell]

I have since found that the easiest way is to use (here for separate files, I’m sure it works within a single file too):

TChain ch("TreeName")
ch.AddFile("file1.root",TChain::kBigNumber,"directory1/TreeName")
ch.AddFile("file2.root",TChain::kBigNumber,"directory2/TreeName")
ch.Draw("x")

Added this in case anyone else searches this in the future