root_output.py

#!/usr/bin/env python3
 
 
 
import os
from basf2 import create_path, process, B2FATAL, set_random_seed
from ROOT import TFile
 
set_random_seed("something important")
 
# Create paths
main = create_path()
# Add modules to paths
main.add_module("EventInfoSetter", expList=[1, 1], runList=[1, 2], evtNumList=[100, 100])
main.add_module("EventInfoPrinter")
main.add_module("RootOutput", outputFileName='root_output_test.root', updateFileCatalog=False)
 
# Process events
process(main)
 
# check whether output file contains correct number of events
tfile = TFile('root_output_test.root')
tree = tfile.Get('tree')
if tree.GetEntries() != 200:
    B2FATAL('Created output file contains wrong number of events!')
 
os.remove('root_output_test.root')