Hello, thank you very much for you last suggestion!
I have another problem
At the moment I write the new tree on a new file I get the message:
[color=blue]terminate called after throwing an instance of 'std::bad_alloc’
what(): std::bad_alloc
Aborted (core dumped)[/color]
What can I do?
My program is very simple, it opens a chain of files and loops on all the events.
When an event satisfies my
[color=blue]if (//conditions)[/color]
the new tree is filled:
[color=blue]new->Fill(); [/color]
I’m compiling with the command:
[color=blue]c++ name.C -o name.exe root-config --libs --cflags -Wall[/color]
When did you create the output file compare to when you create the output TTree? (Most likely the tree ‘new’ is not associated with a file and fill up you RAM).
Thank you very much Philippe for your reply.
In my program I open a new file just after the loop on the events is finished and try to write my new tree on it using:
[color=blue]newtree->Write(); [/color]
Perhaps the program is written in a too much naive way…
I attach it, if somebody can have a look you are very kind.
Elena svenTrees.C (21.3 KB)
Indeed, you must create/open the file before you call to CloneTree: TFile *f = new TFile("sel8-03_dqcuts_1.root","recreate");
TTree *qt = chain.CloneTree(0);Otherwise you dataset will be fully loaded in memory and this will failed if your machine does not have enough memory.
