I have two ROOT files each containing the same number of entries and the same branches. I would like to combine these files but not by appending the entries from one onto the other (like hadd does) but rather I would like the corresponding entries from the files to be combined into one larger entry. So the number of entries in the final file is the same but, for example, if each original file contained a vector of 20 four-vectors in each event, then each event in the final file would contain a vector of 40 four-vectors.
I can write a script to do this, but I am simply wondering if there already exists a utility to do this (like hadd) and if so, if someone could point me to it?
Thanks in advance,