B2A105-SimulateAndReconstruct-withBeamBkg.py

#!/usr/bin/env python3
 
 
 
 
 
import basf2 as b2
from modularAnalysis import inputMdst
from simulation import add_simulation
from reconstruction import add_reconstruction
from mdst import add_mdst_output
import glob
import os
 
# create a path
my_path = b2.create_path()
 
# load input ROOT file
inputMdst(filename=b2.find_file('B2A101-Y4SEventGeneration-evtgen.root'), path=my_path)
 
# background files
# location of the files is obtained from a shell variable - check first if it is set
if 'BELLE2_BACKGROUND_DIR' not in os.environ:
    b2.B2FATAL(
        'BELLE2_BACKGROUND_DIR variable is not set. \n'
        'Please export (setenv) the variable to the location of BG overlay sample. \n'
        'Check https://confluence.desy.de/display/BI/Beam+background+samples to find them')
# get list of files and check the list length
bg = glob.glob(os.environ['BELLE2_BACKGROUND_DIR'] + '/*.root')
if len(bg) == 0:
    b2.B2FATAL('No files found in ', os.environ['BELLE2_BACKGROUND_DIR'])
 
# simulation
add_simulation(path=my_path, bkgfiles=bg)
 
# reconstruction
add_reconstruction(path=my_path)
 
# dump in MDST format
add_mdst_output(path=my_path,
                mc=True,
                filename='B2A101-Y4SEventGeneration-gsim-BKGx1.root')
 
# Show progress of processing
my_path.add_module('ProgressBar')
 
# Process the events
b2.process(my_path)
 
# print out the summary
print(b2.statistics)