Copy directory from one file to another

ROOT
1

Hi,

May I ask you some help about the following problem I face:

I have two rootfiles containing many directories which in turns contains sub-directories, histograms and vectors.

I would like to create a new file containing a copy of some directories of the first file and of some other directories of the second file.

Exemple:

If first file is f1 and contains directories d1_1, d1_2, d1_3, d1_4, …
and if second file f2 contains directories d2_1, d2_2, d2_3, …

I would like to create a third file f3 containing d1_1, d1_4 and d2_6.

Is this possible ? I hope my failures to do this are only due to the lack of expertise in C++ and Root.

Thanks in advance for any help you can provide,

Pierre

2

Hello Pierre,

Here is one way to do it:

(I assume that f1 and f2 are TFile pointers holding the addresses of you original files)

TFile* f3=new TFile(“f3.root”,“create”)
f3->WriteObject( f1->GetDirectory(“d1_1”), “d3_1”)
f3->WriteObject( f1->GetDirectory(“d1_4”), “d3_2”)
f3->WriteObject( f2->GetDirectory(“d2_6”), “d3_3”)
f3->Write()
delete f3

Best regards
John

3

see my anser to the Discussion Forum at:
root.cern.ch/phpBB2/viewtopic.php?t=2789

Rene

4

Hi, I think the link is broken (error 404 !).

5

Unfortunately we moved the forum from phpBB2 to discourse and, in that particular case, we lost the connection with the old René’s post.