PYTHON与JAVA执行时间对比

基本类

PYTHON

import time

start_time = time.time()

n = int(input())
jie = 1
sum = 0
i = 1
while n >= i:
    jie = jie * i
    sum = sum + jie
    i = i + 1
print(sum)

end_time = time.time()
 
print("程序执行时间为：", end_time - start_time, "秒")

执行结果

程序执行时间为： 0.00101470947265625 秒

JAVA

    public static void main(String[] args) {
        double st = System.nanoTime() / 1000000000.0;
        long jie = 1;
        long sum = 0;
        for (int i = 1; i <= 4000; i++) {
            jie = jie * i;
            sum = sum + jie;
        }
        System.out.println(sum);
        double et = System.nanoTime() / 1000000000.0;
        System.out.println("程序执行时间为：" + (et - st) + "秒");
    }

执行结果

程序执行时间为：1.868999097496271E-4秒

结论

JAVA的执行要比PYTHON快。

大数据工具类

PYTHON

使用了基于C语言编写的工具类，这里以NumPy为例。

import time
import numpy as np

start_time = time.time()

for j in range(10):
	big_data = np.random.randint(0, 1000000, size=1000000)

	# 计算数组的平均值
	mean_value = np.mean(big_data)
	print(mean_value)
 
	# 计算数组的标准差
	std_deviation = np.std(big_data)
	print(std_deviation)

	# 对数组进行排序
	#sorted_data = np.sort(big_data)
	#print(sorted_data)

	# 计算每个元素的平方
	squared_data = np.square(big_data)
	print(squared_data)

end_time = time.time()
 
print("程序执行时间为：", end_time - start_time, "秒")

执行结果

程序执行时间为： 0.10068464279174805 秒

JAVA

    public static void main(String[] args) {
        double st = System.nanoTime() / 1000000000.0;
        for (int i = 0; i < 10; i++) {
            bigData();
        }
        double et = System.nanoTime() / 1000000000.0;
        System.out.println("程序执行时间为：" + (et - st) + "秒");
    }
    public static void bigData() {
        Random random = new Random();
        int[] randomArray = new int[1000000];
        for (int i = 0; i < 1000000; i++) {
            randomArray[i] = random.nextInt(1000000);
        }
        System.out.println(calculateAverage(randomArray));
        System.out.println(calculateStandardDeviation(randomArray));
        square(randomArray);
    }
    public static double calculateAverage(int[] arr) {
        if (arr == null || arr.length == 0) {
            throw new IllegalArgumentException("数组为空");
        }
        int sum = 0;
        for (int num : arr) {
            sum += num;
        }
        return (double) sum / arr.length;
    }
    public static double calculateStandardDeviation(int[] numbers) {
        double mean = calculateAverage(numbers);
        double sumOfSquaredDifferences = 0.0;
        for (int number : numbers) {
            sumOfSquaredDifferences += Math.pow(number - mean, 2);
        }
        return Math.sqrt(sumOfSquaredDifferences / numbers.length);
    }
    public static void square(int[] numbers) {
        for (int i = 0; i < numbers.length; i++) {
            numbers[i] = numbers[i] * numbers[i];
        }
    }

执行结果

程序执行时间为：0.12971409992314875秒

结论

PYTHON的执行要比JAVA快，并且执行的内容越多差距越大。