Pass multiple parameters to concurrent.futures.Executor.map?

Question

The concurrent.futures.Executor.map takes a variable number of iterables from which the function given is called. How should I call it if I have a generator that pro

Answer 1

For ProcessPoolExecutor.map():

Similar to map(func, *iterables) except:

the iterables are collected immediately rather than lazily;

func is executed asynchronously and several calls to func may be made concurrently.

Try running the following snippet under python 3, and you will be quite clear:

from concurrent.futures import ProcessPoolExecutor

def f(a, b):
    print(a+b)

with ProcessPoolExecutor() as pool:
    pool.map(f, (0, 1, 2, 3, 4, 5, 6, 7, 8, 9), (0, 1, 2))

# 0, 2, 4

array = [(i, i) for i in range(3)]
with ProcessPoolExecutor() as pool:
    pool.map(f, *zip(*array))

# 0, 2, 4