Question

I have a function that takes multiple arguments, some of which are boolean. I’m trying to pass this to the multiprocessing pool.apply_async and want to pass some args with the names attached.

Here’s an example script that I’m working with:

from multiprocessing import Pool

    def testFunc(y, x, calcY=True):
        if calcY == True:
            return y*y
        elif calcY == False:
            return x*x

    if __name__ == "__main__":
        p = Pool()
        res = p.apply_async(testFunc, args = (2, 4, False))
        print res.get()

This works, but I’m curious about changing the res = p.apply_async(testFunc, args = (2, 4, False)) to something like:

res = p.apply_async(testFunc, args = (2, 4, calcY = False))

Answer 1

apply_async has args and kwds keyword arguments which you could use like this:

res = p.apply_async(testFunc, args=(2, 4), kwds={'calcY': False})