How to run two threads simultaneously?

Question

from threading import Thread
import time
class ThreadTest():

    def loop1(self):
        for i in range(0, 100, 5):
            print(i)
            time.sleep(2)

    def loop2(self):
        for i in range(100, 210, 11):
            print(i)
            time.sleep(2)

if __name__ == '__main__':
    T1 = Thread(target=ThreadTest().loop1(), args=())
    T2 = Thread(target=ThreadTest().loop2(), args=())
    T1.start()
    T2.start()
    T1.join()
    T2.join()

The above code runs the methods in sequence rather than simultaneously. I want a way where I can run two method/process simultaneously.

score 6 · Accepted Answer · answered Dec 19 '17 at 23:16

Simple bug in your code.

Replace:

T1 = Thread(target=ThreadTest().loop1(), args=())
T2 = Thread(target=ThreadTest().loop2(), args=())

With:

T1 = Thread(target=ThreadTest().loop1, args=())
T2 = Thread(target=ThreadTest().loop2, args=())

Because you're calling the functions loop1() and loop2() in the main thread, they're going to run sequentially. You want to point to the functions, without actually calling them so the subthreads can call them themselves.

How to run two threads simultaneously?

1 Answers1