A question about hadd

Dear rooters:
I have about 400 data files and in each data file, there is a tree which includes 25 branches. Unfortunately, some of these files are updated later and one more branch is added, which means in some data files, the tree includes 26 branches. When I merge all these data files with hadd, I am told that this file is skipped because of the different branch number. Is there any way to ignore this new branch and merge all the files with only the old 25 branches?


1 Like


You need to disable the ‘fast’ merging. To do so, request different compression level:

hadd -f2 target.root source.root source2.root


1 Like