Reusing the automatic histogram

William Love (love@bnl.gov)
Thu, 15 Apr 1999 17:12:25 -0400


Rooters

I am trying to use in a loop the automatic binning feature of
ntuple->Draw("x>>h1","selection")

If I try to reuse h1 without deleting it the contents are replaced
but the bins and limits are not recalculated which is no use. If
I delete h1 before replacing it, new limits are computed but I get a
segmentation violation.

root [0] TFile f("straight3rd.root");
root [1] stks->Draw("z>>h1","z>28 && z<32");
Warning in <MakeDefCanvas>: creating a default canvas with name c1
root [2] h1->Print();
TH1.Print Name= h1, Total sum= 18409
root [3] h1->Delete();
root [4] stks->Draw("z>>h1","z>55 && z<60");
root [5] h1->Print();

*** Break *** segmentation violation

Help?

Bill Love