Adding histograms

ROOT
1

Hi,

I was wondering if i can get help to solve a simple problem in root. I have four different histograms in four different folders. I want to add them up. Can someone please help me how to do it?

Thanks in advance!

2

Hi,

the method you are looking for is TH1::Add. In code:

histo1.Add(histo2);
histo1.Add(histo3);
histo1.Add(histo4);

Cheers,
D

3

Thanks for reply. I have another problem. My histograms are in different folders e.g, histo 1 is in one folder and histo 2 is in another folder. I am wondering how can i set the path for those histograms?

cheers

4

You should “cd” in each folder, "Get’ the histogram you need in that folder and do the Add once you have got all them.

5

… Or simply input the full path into the Get or GetObject methods of TFile.

Cheers,
D