To copy a set of events from one file to another, use copyd0om.py You can do a lot of things, like skip events, or select events, etc. For an up-to-date list of options, use the -help option. Usage: copyd0om.py - Input file. - Output file (optional). - Options Known options: -dump - Dump Chunks. -id - Dump Collision id's. -skip n - Skip n events. -copy n - Copy n events. -files n - Copy at most n files. -max_per_file n - Maximum n events per file (for file splitting). -only_collids r1 e1 r2 e2 ... - Collision ids. to select. -skip_collids r1 e1 r2 e2 ... - Collision ids. to skip. -sync - Synchronize output file advance with input files. -input_files_per_file - Number of input files per output file. -oform - Output format (DSPACK or EVPACK). -comp n - Compression level (non-zero implies -oform EVPACK). -sort type - Sort type (sequential, numeric, reverse_sequential, reverse_numeric, random) -veto - Output filter veto classes. -write - Output filter write classes. -chunks - Output filter write chunks. -embed_defs - Embed a dspack dictionary in each evpack record. -status_file - Specify status file. -status_level n - Specify status level.