Hi all,
I am trying to create a new histogram (hist_new)
via normalizing the bin content from another histogram (hist_old
). As a first step I am trying to access the ROOT file and clone (hist_old
) but for some reason I get a null pointer error. May you please help me with this?
Here is part of my python script:
def fillPileupHistogram (lumiInfo, calcOption, hist, minbXsec, Nbins):
f = ROOT.TFile.Open(options.bb,'r')
ROOT.TH1.AddDirectory(0)
hist_old = f.Get("BX distribution for fill " + str(fill_num))
hist = hist_old.Clone()
f.Close()
return hist
_ROOT Version:_6.10/09
Platform: CERN remote host
Compiler: python
___Preformatted text