Exception: bad allocation
Error: Symbol G__exception is not defined in current scope (tmpfile)(1)
Error: type G__exception not defined FILE:(tmpfile) LINE:1
(Long64_t)0
*** Interpreter error recovered ***
Hi gdule, according to my limited ROOT experience, “bad allocation” error usually means you’re running out of memories allowed per process in you system. My suggestion would be do not combine those trees and analyze them separately.
The hadd executable is a bash command comes with ROOT installation. You may use it like this: $ hadd output_file_name input_filename_1 input_filename_2 …
just to come back to my previous question: are all the files you are listing physically on disk and not corrupted? Can you identify acting on the max number of iteration the file at which the issue appears and inspect the file which is linked to the problem?