python如何加速计算密集型任务2?
问题描述:
在python中,有一个函数,其功能是进行某种计算,需要传入一些参数,计算完成后传回结果,参数是a,b,c,d,分别从列表中取值,返回值是xx,yy,分别是一个列表,调用其一次大概要1s的时间,现在需要通过for循环调用其350次,保存每次调用结果(可能是合并成一个列表),腺癌要加速该代码?
使用 multiprocessing 模块:
from multiprocessing import Poolimport time# 假设这是你的函数def compute(a, b, c, d):# 这里是计算过程,我们假设计算需要1秒import timetime.sleep(1) # 模拟耗时的计算xx = [a, b]yy = [c, d]return xx, yy# 这是你的参数列表A = list(range(1, 351)) # 从1到350的整数列表B = [i * 2 for i in A] # 假设B是A的两倍C = [i * 3 for i in A] # 假设C是A的三倍D = [i * 4 for i in A] # 假设D是A的四倍# 将A, B, C, D组合成参数对params = [(a, b, c, d) for a, b, c, d in zip(A, B, C, D)]# 使用 multiprocessing 的 Pool 来并行计算if __name__ == '__main__':start_time = time.time() # 记录开始时间with Pool(processes=4) as pool: # 你可以根据你的 CPU 核心数来设置进程数results = pool.starmap(compute, params)end_time = time.time() # 记录结束时间# 合并结果all_xx = [result[0] for result in results]all_yy = [result[1] for result in results]# 打印结果的一部分以验证print("First few xx:", all_xx[:5])print("First few yy:", all_yy[:5])# 打印执行时间print(f"Execution time: {end_time - start_time:.2f} seconds")
使用concurrent.futures模块:
from concurrent.futures import ProcessPoolExecutorimport time# 假设这是你要调用的计算密集型函数def compute(a, b, c, d):time.sleep(1) # 模拟计算过程xx = [a, b] # 模拟计算结果yy = [c, d] # 模拟计算结果return xx, yy# 主函数def main():start_time = time.time()# 参数列表A = list(range(1, 351))B = [i * 2 for i in A]C = [i * 3 for i in A]D = [i * 4 for i in A]params = list(zip(A, B, C, D)) # 将四个列表组合成一个参数列表# 结果列表results = []# 使用ProcessPoolExecutor创建进程池with ProcessPoolExecutor() as executor:# 使用executor.map并行执行函数results = list(executor.map(compute, *zip(*params)))end_time = time.time()print(f"Total time taken: {end_time - start_time} seconds")# 合并结果all_xx = [result[0] for result in results]all_yy = [result[1] for result in results]print(f"First few xx: {all_xx[:10]}") # 打印前10个xx结果作为示例print(f"First few yy: {all_yy[:10]}") # 打印前10个yy结果作为示例if __name__ == "__main__":main()
输出:
Total time taken: 88.80965089797974 secondsFirst few xx: [[1, 2], [2, 4], [3, 6], [4, 8], [5, 10], [6, 12], [7, 14], [8, 16], [9, 18], [10, 20]]First few yy: [[3, 4], [6, 8], [9, 12], [12, 16], [15, 20], [18, 24], [21, 28], [24, 32], [27, 36], [30, 40]]
