return value of multiprocessing and extract it as an input of another function in python

Question

from multiprocessing import Pool
a=[1,2,3,4,5,6]
def func1(a):
    return a**2

def func2(a):
    x= np.zeros(1)
    for i in a:
        x += i
    return x
if __name__ == "__main__":
    pool = Pool( os.cpu_count())
    results = pool.map(func1, a)
    print(results)

and then I need

func2(results)

This is just a simple example of my problem. Please don't tell me to transfer a to numpy array first because my func2 is way more complicated than this example. Does anyone know how to do it please?

Thank you very much.

Answer 1

Maybe you are looking for something in this direction:

import multiprocessing as mp
import numpy as np

def func1(n):
    return n ** 2

def func2(a):

    pool = mp.Pool(mp.cpu_count())

    results = pool.map(func1, a)

    pool.close()
    pool.join()

    print(results)
    # [1, 4, 9, 16, 25, 36]

    x = np.sum(results)
    return x


if __name__ == "__main__":
    a = [1, 2, 3, 4, 5, 6]
    
    out = func2(a)
    print(out)
    # 91