Ed,
I do not understand this problem. Coiuld you send me a complete
test example?
Rene Brun
On Fri, 28 Jun 2002, Ed Oltman wrote:
> Hello,
>
> I am getting some Error messages when I write an TNtuple to a root file that
> I
> don't understand. The good news is that the write operation works.
> However, I suspect that I am missing something important here.
>
> Here is what I do:
>
> TFile *f = new TFile("c:\\root\\ap.root");
> TNtuple *pIn = (TNtuple *)f->Get("pntup");
> .
> .
> .
> TNtuple *pOut = new TNtuple("pOut","x:y:z:a");
> pOut->SetDirectroy(0); // keep ntuple "memory resident"
> .
> use pIn data to populate pOut ntuple
> .
>
> At some point, I decide to save pOut. This is what I do:
>
> TDirectory *pSave = gDirectory;
> gDirectory->pwd();
> TFile *pF = new TFile("fft0600_0600.root","RECREATE");
> gDirectory->pwd();
> TNtuple *pClone = (TNtuple *)pOut->CloneTree();
> pClone->Write();
> pF->Close();
> delete pF;
> gDirectory = pSave;
> gDirectory->pwd();
>
> and here is the output I get when I execute save-to-file code:
>
> c:\root\ap.root:/
> fft0600_0600.root:/
> Error in <TBranch::Write>: File c:\root\ap.root is not writable
> Error in <TBranch::Write>: File c:\root\ap.root is not writable
> Error in <TBranch::Write>: File c:\root\ap.root is not writable
> Error in <TBranch::Write>: File c:\root\ap.root is not writable
> c:\root\ap.root:/
>
> It is true that c:\root\ap.root is not writable, but why do I get this
> error?
> When I later try to open fft0600_0600.root, I can read the ntuple withoug
> problem.
>
>
> Thanks,
>
> Ed Oltman
>
>
This archive was generated by hypermail 2b29 : Sat Jan 04 2003 - 23:50:58 MET