prescale.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
 
import basf2
basf2.set_random_seed(501)
 
 
class CountEvents(basf2.Module):
    """Count the number of events passing this module"""
 
    def initialize(self):
        """Start number of events at zero"""
        
        self.num_events = 0
 
    def event(self):
        """Increment number of events each event"""
        self.num_events += 1
 
 
input_events = 1000
expected_success_events = 6
 
main = basf2.Path()
main.add_module("EventInfoSetter", evtNumList=[input_events], expList=[0], runList=[0])
prescale_mod = main.add_module('Prescale', prescale=0.01)
 
success_path = basf2.Path()
success_count = success_path.add_module(CountEvents())
prescale_mod.if_true(success_path)
 
basf2.process(main)
 
print(basf2.statistics)
 
assert success_count.num_events == expected_success_events