Hi Dmitri,
If you run the small example sent in my previous mail, you will get this output
******************************************************************************
*Tree :tree : a test *
*Entries : 1000 : Total = 375172 bytes File Size = 46370 *
* : : Tree compression factor = 8.09 *
******************************************************************************
*Br 0 :Clones_ : Clones_/I *
*Entries : 1000 : Total Size= 0 bytes File Size = 0 *
*Baskets : 0 : Basket Size= 32000 bytes Compression= 1.00 *
*............................................................................*
*Br 1 :Clones.fUniqueID : fUniqueID[Clones_]/i *
*Entries : 1000 : Total Size= 187598 bytes File Size = 42850 *
*Baskets : 6 : Basket Size= 32000 bytes Compression= 4.38 *
*............................................................................*
*Br 2 :Clones.fBits : fBits[Clones_]/i *
*Entries : 1000 : Total Size= 187574 bytes File Size = 3520 *
*Baskets : 6 : Basket Size= 32000 bytes Compression= 53.29 *
*............................................................................*
You can see that 3 branches are produced:
Clones_ contains the TClonesArray counter. All the data in this branch
fit nicely in memory (no basket written to the file). The buffer
will be Streamed with the tree header in tehe main file.
Clones.fUniqueID: has 6 baskets written to test.clones.root. Like for Clones_
the remaining buffer in memory will be Streamed with the Tree header.
Clones.fBits: same as Clones.fUniqueID.
As a result, look at the result of the following few commands:
root [0] TFile f("test.root")
root [1] tree->GetBranch("Clones.fBits")->GetFileName()
(const char* 0x887e51c)"test.clones.root"
root [2] tree->GetBranch("Clones.fUniqueID")->GetFileName()
(const char* 0x88723ec)"test.clones.root"
root [3] tree->GetBranch("Clones_")->GetFileName()
(const char* 0x403b458c)""
root [4] tree->GetBranch("Clones")->GetFileName()
(const char* 0x403b458c)""
I will implement TBranchClones::SetFile to make the implicit loop on
all subbranches of the TClonesArray.
Rene Brun
Dimitri Peressounko wrote:
>
> Dear Rene,
>
> I try your example with one more line:
> br->SetFile("test.clones.root");
> and obtained exacly the same result as before:
>
> root [0] TFile * f = new TFile("test.root")
> root [1] TTree * t = (TTree*) f->Get("tree")
> root [2] t->GetBranch("Clones")->GetFileName()
> (const char* 0x403ff98c)""
>
> May be I am missing something? Why GetFileName is empty?
>
> Dmitri.
>
> On Tue, 27 Mar 2001, Rene Brun wrote:
>
> > Hi Dimitri,
> >
> > TBranch::SetFile acts on one branch only, not on its sub branches.
> > In the case of a TClonesArray, one has to loop on all the subbranches as shown
> > in the example below.
> > Note that in case you have a few entries only, data are buffered in
> > the branch baskets. If all the buffers fit in memory, they are written
> > in one single block together with the tree header on the master file.
> > In this case, the associated files will be empty.
> >
> > Rene Brun
> >
> >
> > {
> > TFile * f = new TFile("test.root","recreate");
> > TClonesArray *d = new TClonesArray("TObject",10);
> > TTree * t = new TTree("tree","a test");
> > TBranch *br = t->Branch("Clones",&d,32000);
> > TIter next(br->GetListOfBranches());
> > TBranch *brc;
> > while((brc=(TBranch*)next())) {
> > brc->SetFile("test.clones.root");
> > }
> > for (Int_t i=0;i<1000;i++) {
> > for (Int_t j=0;j<(i%50);j++) {
> > TObject *obj = new ((*d)[j]) TObject();
> > obj->SetUniqueID(100*i+j);
> > }
> > t->Fill();
> > }
> > t->Print();
> > t->Write();
> > }
> >
> >
> > Dimitri Peressounko wrote:
> > >
> > > Hi, Rooters!
> > >
> > > I am trying to divert branch ot TClonesArray to separate file:
> > >
> > > root [0] TFile * f = new TFile("test.root","new")
> > > root [1] TClonesArray * d = new TClonesArray("TObject",10)
> > > root [2] TTree * t = new TTree("tree","a test")
> > > root [3] TBranch * br = t->Branch("Clones",&d,32000);
> > > root [4] br->SetFile("test.clones.root")
> > > root [5] t->GetBranch("Clones")->GetFileName()
> > > (const char* 0x858a01c)"test.clones.root"
> > > root [6] t->Fill()
> > > (Int_t)4
> > > root [7] t->Write()
> > > (Int_t)761
> > > root [8] .q
> > >
> > > Now I am reading back this branch and find, that file = "".
> > >
> > > root [0] TFile * f = new TFile("test.root")
> > > root [1] TTree * t = (TTree *) f->Get("tree")
> > > root [2] t->GetBranch("Clones")->GetFileName()
> > > (const char* 0x403ff98c)""
> > >
> > > file test.clones.root is not created as well.
> > > What I am doing wrong?
> > >
> > > Dmitri
> >
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