Loop over subdirectories of a rootfile in pyRoot

[Newbie]

Hi,

I have the following structure in a root file containing subdirectories with TH1’s:

rootfile.root
subdir1
h_1
h_2
…
subdir2
subdir3
…

I want to normalise all the histograms with a scale factor, is there any clean way to loop over all the subdirectories and histograms without hardcoding in pyRoot? I tried “keys” but it gives only the names of the subdirectories and I couldn’t get the TH1’s.

Thanks!

[etejedor]

Hello,
Can you check if the final solution discussed here works for you?

Loop over all objects in a ROOT file

Since I found both replies being broken in my case. In particular, IsFolder() returns True for TTree, GetListOfKeys() chokes with TTree, etc, so pasting my longer solution here: import ROOT def Map(tf, browsable_to, tpath=None): """ Maps objets as dict[obj_name][0] using a TFile (tf) and TObject to browse. """ m = {} for k in browsable_to.GetListOfKeys(): n = k.GetName() if tpath == None: m[n] = [tf.Get(n)] else: m[n] = [tf.Ge…

Cheers,
Enric