I have a series of ROOT files which contain event data from our experiments at the ANU (typical experiments in the current series use 5 particle detectors, four gamma detectors and 4 TDCs).
I have experience of producing subset files from the main ROOT file using TCut on the basis of various attributes of the data (e.g. for data lying between certain limits).
I need to divide the event data so that the first 1 Mb of event data goes into one file, the next 1Mb of event data into the next file and so on. I want to do this without losing the relationships between the data (e.g. coincidences between gamma and particle data).
An example ROOT file with the same structure as the files I want to cut up is attached.
I have no idea where to start on this. I have tried using circular buffers but I can’t seem to get the syntax correct.
Any guidance you can give on an appropriate method will be greatly appreciated. pd1060309_r12.root (1.75 MB)
I tried using TFile::SetMaxTreeSize() in one of my attempt as it does seems perfect (I also tried SetCircular) - I must be using it incorrectly because I did not get the expected effect.
Is there an example of this command being used in a script that I could look at to see where I might be going wrong?
I will post a short script (that runs) later today to illustrate my problem. It could simply be that I am misinterpreting how the command is meant to work.
It is all working now - the problem was that I was miscounting the zeros in my TTree::SetMaxTreeSize command. This meant that I was telling ROOT to split a 50Mb into 50Mb chunks and nothing was happening.