Write of delete part of a tree

ROOT
1

Hello,

I’m running a data acquisition and saving all my events as a Tree. Sometimes I get “bad” events which have to be thrown away. I can only check if there were bad events every few seconds. So every few seconds I know that my N previous events (which were accumulated since the last check) are either good or bad. I want to either discard them or save, possibly fast (without copying the whole Tree to another one or so). How to do it with a Tree?

Yuri.

2

Hi,

you could maintain a TEntryList, writing it very regularly to a separate file (for crash recovery). Once the tree is done (e.g. at the end of a file) you can post-process the tree and clone only the selected entries.

Cheers, Axel.