TEntryList with TChain and identical tree names

ROOT
1

Hello,

Suppose you have a root file with two trees with the same name but in a different directory:

file.root
 * dirA/treename
 * dirB/treename

Now, creating a chain with the two trees is not an issue. However, creating an entry list with chain.Draw(">>elist", …) only contains entries from one of the trees. I suspect this is “by design” as the documentation of TEntryList says “Trees and lists are matched by the TTree name and its file name (full path)”.

Is there a workaround for this use case? Is a fix feasible in the near future?

Thanks,
Rosen

2

Hi Rosen,

I can reproduce the issue you report: there is an action on the ROOT side to find a proper solution: I’ll get back to you. Meanwhile, a quick workaround if you are using linux/mac could be creating a symlink to the file where the trees are stored in order to differentiate the two trees.

Cheers,
Danilo

3

Hi Danilo,

Thanks for looking into it. That’s a clever workaround, I’ll use it!

Cheers,
Rosen

4

Hi Rosen,

for your information, this has been fixed in the master: sft.its.cern.ch/jira/browse/ROOT-7036

Cheers,
Danilo