Memory Leak and TGraph slider question

Eddy Offermann (eddy@rentec.com)
Wed, 30 Sep 98 17:40:50 EDT


Dear Root-ers,

two questions:

1) two weeks ago, I had a question concerning cleanup of objects.
The answer of Rene Brun seems only to solve part of the problem:
the program does not crash anymore but we still have
a memory leak. Below is a macro that makes a root file, followed
by a macro that keeps on opening and closing it.
Even when I comment out the "cd" and "tree" statements, the
program size keeps growing.
Maybe it is silly to be worried about an increase of 1Mb after about
opening/closing 1000 files but if anybody could shed some light
on this, I would appreciate it.

make()
{
gROOT->Reset();

TFile *hfile = new TFile( "foo.root", "RECREATE" );
TDirectory *sub = hfile->mkdir("sub");
sub->cd();
TTree *tree = new TTree( "tree", "tree" );

Int_t tmp = 100;
Int_t split = 1;
Int_t bsize = 64000;
TBranch *branch = tree->Branch("branch", &tmp, "", bsize);
tree->Fill();

hfile->Write();
delete tree;
hfile->Close();
delete hfile;
}

read()
{
for (Int_t i=1; i >0; i++)
{
printf("%d\n",i);

TFile *hfile = new TFile("foo.root","READ");
hfile->cd("sub");

TTree *tree = (TTree*) gDirectory->Get("T");
delete tree;

hfile->Close();
delete hfile;
}
}

2) I have problems using the slider on "Tgraph" objects. Running,
for instance, graph.C in the tutorials-directory, selecting
with my mouse the graph, choosing DrawPanel, results in the message:

root [1] Error in <TClass::GetMethod>:
Did not find matching TMethod <GetOption> with "" for TGraph

However, using the slider in the FitPanel does result in a
different fitting region.

Is there another way to zoom-in on a graph ??

Best regards,
Eddy