同时运行两个带参数和返回列表的函数？

Question

据我所知,两个功能可以并行使用运行multiprocessing或threading模块,例如使在同一时间运行两个功能和Python的多重并行进程.

但以上示例仅使用打印功能.是否有可能在python中运行并行返回列表的函数,如果是,如何？

我尝试过使用线程:

from threading import Thread
def func1(x):
    return [i*i for i in x]

def func2(x):
    return [i*i*i for i in x]

nums = [1,2,3,4,5]

p1 = Thread(target = func1(nums)).start()
p2 = Thread(target = func2(nums)).start()

print p1
print p2

但我得到了以下错误:

Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 808, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/threading.py", line 761, in run
    self.__target(*self.__args, **self.__kwargs)
TypeError: 'list' object is not callable

None
None
Exception in thread Thread-2:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 808, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/threading.py", line 761, in run
    self.__target(*self.__args, **self.__kwargs)
TypeError: 'list' object is not callable

我已经尝试输入args参数作为元组,而不是变量:

import threading
from threading import Thread

def func1(x):
    return [i*i for i in x]

def func2(x):
    return [i*i*i for i in x]

nums = [1,2,3,4,5]

p1 = Thread(target = func1, args=(nums,)).start()
p2 = Thread(target = func2, args=(nums,)).start()

print p1, p2

但它只返回None None,所需的输出应该是:

[OUT]:

[1, 4, 9, 16, 25] [1, 8, 27, 64, 125]

Answer 1

线程的目标函数不能返回值.或者,我应该说,该return值被忽略,因此,不会传回产卵线程.但是这里有几件事你可以做:

1)使用返回产卵线程Queue.Queue.请注意原始函数的包装:

from threading import Thread
from Queue import Queue

def func1(x):
    return [i*i for i in x]

def func2(x):
    return [i*i*i for i in x]

nums = [1,2,3,4,5]

def wrapper(func, arg, queue):
    queue.put(func(arg))

q1, q2 = Queue(), Queue()
Thread(target=wrapper, args=(func1, nums, q1)).start() 
Thread(target=wrapper, args=(func2, nums, q2)).start() 

print q1.get(), q2.get()

2)global用于访问线程中的结果列表以及产生过程:

from threading import Thread

list1=list()
list2=list()

def func1(x):
    global list1
    list1 = [i*i for i in x]

def func2(x):
    global list2
    list2 = [i*i*i for i in x]

nums = [1,2,3,4,5]

Thread(target = func1, args=(nums,)).start()
Thread(target = func2, args=(nums,)).start()

print list1, list2