You should not do:
TTree *TREE = new TTree(...)
TFile *myfile=new TFile(name_ntuple, "RECREATE");
...
TREE->Write();
but
TFile *myfile=new TFile(name_ntuple, "RECREATE");
TTree *TREE = new TTree(...)
...
TREE->Write();
Rene Brun
Matthieu Lechowski wrote:
>
> Hello,
>
> It's not easy to have a simplified version of my code, but if it's
> necessary I will provide you.
>
> I understand why the 2nd solution did not work: actually, I have to
> open a second file where I get data to fill my Tree.
>
> So I have this order of instructions:
>
> TTree *TREE = new TTree(...)
> TFile *data_file = new TFile(name_data_file);
> //..fill tree
> data_file->Close();
>
> TFile *myfile=new TFile(name_ntuple, "RECREATE");
> TREE->Write();
> myfile->Close(); //"delete myfile;" doesn't work
>
> I just have changed the place of data_file->Close(). Indeed it was at
> the end, so when I tried to put "TFile *myfile=new ..." at the top as you
> said, of course the TREE->Write() wanted write in "data_file" instead of
> "myfile" (that's why I had the message "... not writable", I did not see
> that the message concerned "data_file" and not "myfile", sorry).
>
> But even placing data_file->Close() before writing the tree, it does not
> work when I put "TFile *myfile=new ..." at the top.
>
> ----
> In conclusion, I have to manage 2 files, and I want write a Tree in one
> of them. The instructions above work for small files, but not for big
> ones.
> Do you see where could be the problem ?
>
> Matthieu.
>
> On Mon, 29 Sep 2003, Rene Brun wrote:
>
> > I am afraid that we will not make any progress without looking at a simplified
> > version of your code reproducing this problem.
> >
> > Rene Brun
> >
> > Matthieu Lechowski wrote:
> > >
> > > Hello,
> > > Thanks, but unfortunately it doesn't work.
> > > The first solution doesn't change anything, and with the second ROOT
> > > tells me my file is not writable (Error in <TTree::Write>: File ... is
> > > not writable).
> > > Have you others ideas ?
> > > Thank you.
> > >
> > > Matthieu.
> > >
> > > On Fri, 26 Sep 2003, Rene Brun wrote:
> > >
> > > > Matthieu,
> > > >
> > > > This seems to be a problem with the destructor of your TTree when
> > > > you close the file.
> > > > You can try two solutions:
> > > > 1- after TREE.Write(); add the statement
> > > > TREE.SetFile(0);
> > > >
> > > > 2- Do not create your Tree in the stack, but in the heap with
> > > > TFile *myfile=new TFile(name_ntuple, "RECREATE");
> > > > TTree *TREE = new TTRee(...
> > > > //..fill tree
> > > > TREE->Write();
> > > > delete myfile; //do not delete TREE
> > > >
> > > > Rene Brun
> > > >
> > > > Matthieu Lechowski wrote:
> > > > >
> > > > > Hello,
> > > > >
> > > > > ROOT leaves without saying anything when I try to write a TTree in a
> > > > > TFile, and the file has only few bytes (and can not be opened of
> > > > > course).
> > > > >
> > > > > I have a global tree: TTree TREE("T","TREE");
> > > > > In a function, I fill it, then:
> > > > > TFile *myfile=new TFile(name_ntuple, "RECREATE");
> > > > > TREE.Write();
> > > > > myfile->Close();
> > > > >
> > > > > This is the way I always used, and it always worked, but this time I
> > > > > have a big Tree and this doesn't work, I don't know why.
> > > > > Its size is less than the limit 2Gb, I think it should be around 80Mb
> > > > > with 100.000 entries (I have already a similar file of 8Mb with 10.000
> > > > > entries that I succeeded to write).
> > > > >
> > > > > Have you an idea of what goes wrong ?
> > > > > Thank you.
> > > > >
> > > > > Matthieu Lechowski
> > > > > LAL Orsay
> > > > >
> > > > > lxplus
> > > > > ROOTSYS=/afs/cern.ch/sw/root/v3.05.05/rh73_gcc2952/root
> > > >
> >
This archive was generated by hypermail 2b29 : Thu Jan 01 2004 - 17:50:15 MET