一次运行 10 个循环

Question

Okay, so I can do this in PowerShell as that is my specialty, however, I having issues trying to accomplish this in Python.

See my PowerShell example here on what I am trying to do.

Essentially this is what I am trying to do in pseudo-code:

objArray = [
    {"name": "Test User", "address": "123 Movie Road"}, 
    {"name": "Test User", "address": "444 Music Road"}
]

#I want to run the below loop 10 at a time

for obj in objArray: 
     print(obj["name"])

Obviously, this is oversimplified however, I hope this outlines what I need to do.

Answer 1

You can use range with a step value.

step = 10
for batch_idx in range(0, len(objArray), step):
    for obj in objArray[batch_idx:(batch_idx + step)]:
        print(obj['name'])

You can extend this using, for example, multithreading:

from threading import Thread

def foo(objects):
    for obj in objects:
        print(obj['name'])

step = 10
for batch_idx in range(0, len(objArray), step):
    objects = objArray[batch_idx:(batch_idx + step)]
    t = Thread(target=foo, args=(objects,))
    t.start()

Answer 2

To execute something in parallel/concurrent you need threads. Luckily Python has an easy to use API for this. You need to import the threading library.

To run an thread you need to create a new Thread object and start it. The Thread object needs at least a target argument, which tells him which function to run.

eg

import threading

def do_something():
    for i in range(10):
        print("Executed in thread")

thread = threading.Thread(target=do_something)

thread.start()

Note that the target must be an executable function. This means only enter pass the name without parenthesis.

To run 10 threads you need to create 10 threads and start them. Your final code could something like this:

import threading

objArray = [
    {"name": "Test User", "address": "123 Movie Road"}, 
    {"name": "Test User", "address": "444 Music Road"}
]


def my_loop():
    for obj in objArray: 
        print(obj["name"])

for i in range(10): 
    thread = threading.Thread(target=my_loop)
    thread.start()