Timer

from fluiddyn.util.timer import Timer, TimerIrregular

Let’s first use the regular timer:

timer = Timer(0.02)

for i in range(10):
    print(f'before tick {i}... ', end='')
    timer.wait_tick()
    print("It's time to tick", i)

before tick 0... It's time to tick 0
before tick 1... It's time to tick 1
before tick 2... It's time to tick 2
before tick 3... It's time to tick 3
before tick 4... It's time to tick 4
before tick 5... It's time to tick 5
before tick 6... It's time to tick 6
before tick 7... It's time to tick 7
before tick 8... It's time to tick 8
before tick 9... It's time to tick 9

Ok. This is the simplest way to use it. But we don’t see when the timer ticked. Let’s print these times:

timer = Timer(0.02)

for i in range(10):
    print(f'before tick {i}... ', end='')
    t_tick = timer.wait_tick()
    print("It's time to tick", i, f'(t = {t_tick:.4f} s)')

before tick 0... It's time to tick 0 (t = 0.0201 s)
before tick 1... It's time to tick 1 (t = 0.0401 s)
before tick 2... It's time to tick 2 (t = 0.0601 s)
before tick 3... It's time to tick 3 (t = 0.0801 s)
before tick 4... It's time to tick 4 (t = 0.1001 s)
before tick 5... It's time to tick 5 (t = 0.1201 s)
before tick 6... It's time to tick 6 (t = 0.1401 s)
before tick 7... It's time to tick 7 (t = 0.1601 s)
before tick 8... It's time to tick 8 (t = 0.1801 s)
before tick 9... It's time to tick 9 (t = 0.2001 s)

Now, we see that it’s ticking regularly… and it seems with a quite good accuracy for many needs.

But what can we do if we need irregular steps between the ticks?

times = [0, 0.05, 0.07, 0.1]
timer = TimerIrregular(times)

for i in range(len(times)-1):
    print(f'before tick {i}... ', end='')
    t_tick = timer.wait_tick()
    print("It's time to tick", i, f'(t = {t_tick:.4f} s)')

before tick 0... It's time to tick 0 (t = 0.0501 s)
before tick 1... It's time to tick 1 (t = 0.0701 s)
before tick 2... It's time to tick 2 (t = 0.1001 s)