I am having a strange issue with ROOT 5.22/00d and I wonder if I should worry about it at all… Here it is.
I create histograms in a separate piece of code, for example using this command:
TH1D *jpsi_eta_loose = new TH1D ("jpsi_eta_loose","jpsi_eta_loose",540,-2.7,2.7);
Then this histogram is filled and saved to a TFile.
Later on, I read the TFile and I do the following:
TH1D* eta_a_l_h = new TH1D("eta_a_l_h","",540,-2.7,2.7); eta_a_l_h->Add(jpsi_eta_loose);
and that’s where ROOT gives me a warning:
Warning in TH1D::Add: Attempt to add histograms with different axis limits
Strangely, I get it only for TH1’s where the xmin and xmax are not integer values.
About this, I have two questions:
- Why is ROOT complaining, since both histo have been created with the same command?
- Should I be worried about this, or should this warning be ignored simply? Still, would be nice to understand it.
Thanks in advance,