asyncio 的结果不符合预期

Question

我正在学习 asyncio 库来完成一些我想完成的任务。我编写了以下代码来自学如何在执行原始任务时切换到另一个任务。正如您在下面看到的，应该执行 summation()，直到满足跳转到 secondaryTask() 的条件。 secondaryTask() 完成后，它应该 return 回到 summation()，希望它能完成。潜在结果应该是 sum=1225 和 mul=24.

import asyncio, time


async def summation():
    print('Running summation from 0 to 50:')
    sum = 0
    for i in range(25):
        sum = sum + i
        if i != 25:
            time.sleep(0.1)
        else:
            await asyncio.sleep(0) # pretend to be non-blocking work (Jump to the next task)
    print('This message is shown because summation() is completed! sum= %d' % sum)


async def secondaryTask():
    print('Do some secondaryTask here while summation() is on progress')
    mul = 1
    for i in range(1, 5):
        mul = mul * i
        time.sleep(0.1)
    await asyncio.sleep(0)
    print('This message is shown because secondaryTask() is completed! Mul= %d' % mul)

t0 = time.time()
ioloop = asyncio.get_event_loop()
tasks = [ioloop.create_task(summation()), ioloop.create_task(secondaryTask())]
wait_tasks = asyncio.wait(tasks)
ioloop.run_until_complete(wait_tasks)
ioloop.close()
t1 = time.time()
print('Total time= %.3f' % (t1-t0))

此代码未按预期执行，因为 sum=300 与 sum=1225 相反。显然，在处理 secondaryTask() 时，summation() 不会继续。如何修改summation()才能在后台对剩余的25个值进行求和？

谢谢

Answer 1

只是你粗心大意。你想运行 summation 从 0 到 50，你的 summation 函数应该是 for i in range(50)

asyncio 的结果不符合预期

Results of asyncio are not as expected

python

asynchronous

python-3.x

python-asyncio