Tchain output problem

ROOT
1

hello;
I wrote a program to combine files ROOT with Tchain

[b]{
gROOT-> Reset();

TChain chain(“Hits”);
chain.Add("/home/root1010.1.root");
…
…
chain.Add("/home/root1010.23.root");
chain.Draw(“posX”);
TFile *f = new TFile("1010.root ", “recreate”);
}
[/b]
my problem in TFile *f = new TFile("1010.root ", “recreate”);

ROOT 1010.root the file is created but empty, there is nothing.

2

Please read documentation of TChain, in particular TChain::Merge ; root.cern.ch/root/html/TChain.html#TChain:Merge
and do:

{ TChain chain("Hits"); chain.Add("/home/root1010.1.root"); ...... .... chain.Add("/home/root1010.23.root"); chain.Merge("1010.root","fast"); }
Rene

3

hello
thank you

but I have the same problem when I add the command
chain.Merge(“1010.root”,“fast”);

the Hits file is created but empty

[code]{
TChain chain(“Hits”);
chain.Add("/home/root1010.1.root");
…
…

chain.Merge(“1010.root”,“fast”);
}
[/code]

4

Hi,

[quote]the Hits file is created but empty
[/quote]
What is the ‘Hits file’ what is it suppose to contain?

Cheers,
Philippe.

5

[quote=“pcanal”]Hi,

[quote]the Hits file is created but empty
[/quote]
What is the ‘Hits file’ what is it suppose to contain?

Cheers,
Philippe.[/quote]

all information from examples posX;posY;posZ

this in one root file

but after chain the Hits is empty

01.png800×550 22.6 KB

6

Hi,

Could you post the shortest RUNNING example that shows how this is failing for you so that we can attempt to reproduce the problem?

Thanks,
Philippe.