TTreeFormula for on-line data sorting

Dear Rooters,

I am developing a On-line analysis code based on ROOT. So the major function is to receiving data from event dispatcher and sorts them and fills some histogram on line on line. It is very easy to be done in a program. But the user does not like this way because it requires changing the program and recompiling it. They prefer setup conditions and histogram outside and let the program fill the histogram automatically.

I think I can fill the event in a TTree and then use TtreeFormula to make the condition. But the problem is that I have to keep all the sorted event. Is there any better way to accomplish this work?

Best regards,



An histogram does not care about the order it is filled in.
How is the sorting affecting your data/result?