Logging and random generator

The logging module

SimQN uses the Python logging package as the logging and data monitor tools. To providing the simulator’s internal states (especially the time), SimQN warps the logging. Users can use the logger from:

import qns.utils.log as log

s = Simulator()

# install the log to the simulator to get simulator's internal status

Users can set the logging level and record logs:

a = 1

log.debug("debug message")
log.info("info message", a)
log.warn("warn message", a+1)
log.error("error message")
log.critical("critical message")

Finally, SimQN provides monitor() for date output. sep sets the separator, the default separator is “,” (like csv files). with_time is a boolean indicating whether add a column to record the simulator’s current time.

log.monitor(data1, date2, date3, with_date = True)
# output: time, date1, date2, date3

With the Timer entity provided by SimQN, it is easy to print the network’s status periodically.

from qns.simulator.simulator import Simulator
from qns.entity.timer.timer import Timer
import qns.utils.log as log

s = Simulator(0, 10, 1000)

# the trigger function is log network status
def trigger_func():
    print("network status")

# set the timer with a period
t1 = Timer("t1", 0, 10, 0.5, trigger_func)

# run the simulation

Random generator’s seed

SimQN uses random library from both Python standard library and numpy when measuring qubits or generating random topologies. To make the simulation results reproducible, SimQN provides set_seed() to fix the random generator’s seed:

from qns.utils.random import set_seed

set_seed(1641801012) # fix the random generator's seed

get_randint(low, high) can generates an random integer in [low, high]; get_rand(low, high) can generate a float random number in [low, high); and get_choice(a) selects an random element in list a.