zero_suppression.py

import basf2
import ROOT
from ROOT import Belle2
import b2test_utils
 
# ====================================================================
# This test does the following:
# 1. Simulate a few hundred ParticleGun events to produce a sample of
#    SVD simhits.
# 2. Use SVDDigitizer with varius zero-suppression cut settings and check
#    that the settings work.
# ====================================================================
 
 
class CheckZS(basf2.Module):
    """Check that SVVDShaperDigits are correctly zero-suppressed."""
 
    def __init__(self, thresholdSN):
        '''initialize python module'''
        super().__init__()
        self.thresholdSN = thresholdSN
        '''SNR threshold'''
 
    def event(self):
        '''event'''
        storedigits = Belle2.PyStoreArray("SVDShaperDigits")
        gc = Belle2.VXD.GeoCache.getInstance()
        for digit in storedigits:
            info = gc.get(digit.getSensorID())
            isU = digit.isUStrip()
            noise_in_e = info.getElectronicNoiseU() if isU else info.getElectronicNoiseV()
            adu_equivalent = info.getAduEquivalentU() if isU else info.getAduEquivalentV()
            noise_in_adu = noise_in_e / adu_equivalent
            threshold_in_adu = self.thresholdSN * noise_in_adu
            samples = digit.getSamples()
            for s in samples:
                if s > threshold_in_adu:
                    break
            else:
                basf2.B2FATAL("Found digit under threshold: {0}".format(digit.to_string()))
 
 
if __name__ == "__main__":
 
    with b2test_utils.clean_working_directory():
 
        basf2.B2INFO('Creating simhits...')
        # We create data separately, so that we can use them in other tests.
 
        create_simhits = basf2.create_path()
        create_simhits.add_module('EventInfoSetter', evtNumList=[50])
        create_simhits.add_module('Gearbox')
        create_simhits.add_module('Geometry', components=['MagneticField', 'SVD'], useDB=False)
        create_simhits.add_module('ParticleGun')
        create_simhits.add_module('FullSim')
        create_simhits.add_module('RootOutput', outputFileName='SimulationForThresholdTest.root',
                                  branchNames=['EventMetaData', 'SVDSimHits', 'SVDTrueHits'])
        with b2test_utils.show_only_errors():
            b2test_utils.safe_process(create_simhits)
 
        basf2.B2INFO('Threshold testing...')
 
        threshold = 3
 
        test_threshold = basf2.create_path()
        # Read generated Simhits and Truehits
        test_threshold.add_module('RootInput', inputFileName='SimulationForThresholdTest.root')
        test_threshold.add_module('Gearbox')
        test_threshold.add_module('Geometry', components=['MagneticField', 'SVD'], useDB=False)
        # Set the threshold.
        test_threshold.add_module('SVDDigitizer', ZeroSuppressionCut=threshold)
        threshold_checker = CheckZS(threshold)
        test_threshold.add_module(threshold_checker)
        with b2test_utils.show_only_errors():
            b2test_utils.safe_process(test_threshold)
 
        basf2.B2INFO('Test done.')