Python 多线程与多进程：实战案例剖析，掌握并发编程的应用技巧

import threading
import os
from PIL import Image, ImageFilter

def process_image(image_path):
image = Image.open(image_path)
image = image.resize((256, 256))
image = image.filter(ImageFilter.SHARPEN)
image.save(image_path)

def main():
# 获取图像文件列表
image_files = os.listdir("images")

# 创建线程池
pool = ThreadPool(4)

# 将图像处理任务分配给线程池
for image_file in image_files:
pool.submit(process_image, ("images/" + image_file, ))

# 等待所有线程完成任务
pool.close()
pool.join()

if __name__ == "__main__":
main()

import multiprocessing
import math

def compute_pi(n):
result = 0
for i in range(n):
result += 4 * (-1)**i / (2*i + 1)
return result

def main():
# 分解科学计算任务
n = 100000000
num_processes = 4
sub_tasks = [n // num_processes] * num_processes

# 创建进程池
pool = multiprocessing.Pool(num_processes)

# 将子任务分配给进程池
results = pool.map(compute_pi, sub_tasks)

# 等待所有进程完成任务
pool.close()
pool.join()

# 汇总子任务的结果
pi = sum(results)

print("π =", pi)

if __name__ == "__main__":
main()