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同一台服务器测试

C      0.04 秒

Java   0.21 秒

PHP  2.06  秒

由此可算出 C 是 java性能的5倍，Java 是 PHP 性能的10倍

C

#include <stdio.h>
#include <sys/time.h>

#define BAILOUT 16
#define MAX_ITERATIONS 1000

int mandelbrot(double x, double y)
{
	double cr = y - 0.5;
	double ci = x;
	double zi = 0.0;
	double zr = 0.0;
	int i = 0;

	while(1) {
		i ++;
		double temp = zr * zi;
		double zr2 = zr * zr;
		double zi2 = zi * zi;
		zr = zr2 - zi2 + cr;
		zi = temp + temp + ci;
		if (zi2 + zr2 > BAILOUT)
			return i;
		if (i > MAX_ITERATIONS)
			return 0;
	}

}

int main (int argc, const char * argv[]) {
	struct timeval aTv;
	gettimeofday(&aTv, NULL);
	long init_time = aTv.tv_sec;
	long init_usec = aTv.tv_usec;

	int x,y;
	for (y = -39; y < 39; y++) {
		printf("\n");
		for (x = -39; x < 39; x++) {
			int i = mandelbrot(x/40.0, y/40.0);
			if (i==0)
				printf("*");
			else
				printf(" ");
		}
	}
	printf ("\n");

	gettimeofday(&aTv,NULL);
	double query_time = (aTv.tv_sec - init_time) + (double)(aTv.tv_usec - init_usec)/1000000.0;
	printf ("C Elapsed %0.2f\n", query_time);
    return 0;
}

Java

import java.util.*;

class Mandelbrot
{
	static int BAILOUT = 16;
	static int MAX_ITERATIONS = 1000;

	private static int iterate(float x, float y)
	{
		float cr = y-0.5f;
		float ci = x;
		float zi = 0.0f;
		float zr = 0.0f;
		int i = 0;
		while (true) {
			i++;
			float temp = zr * zi;
			float zr2 = zr * zr;
			float zi2 = zi * zi;
			zr = zr2 - zi2 + cr;
			zi = temp + temp + ci;
			if (zi2 + zr2 > BAILOUT)
				return i;
			if (i > MAX_ITERATIONS)
				return 0;
		}
	}

	public static void main(String args[])
	{
		Date d1 = new Date();
		int x,y;
		for (y = -39; y < 39; y++) {
			System.out.print("\n");
			for (x = -39; x < 39; x++) {
				if (iterate(x/40.0f,y/40.0f) == 0)
					System.out.print("*");
				else
					System.out.print(" ");

			}
		}
		Date d2 = new Date();
		long diff = d2.getTime() - d1.getTime();
		System.out.println("\nJava Elapsed " + diff/1000.0f);

	}
}

PHP

<?php
define("BAILOUT",16);
define("MAX_ITERATIONS",1000);

class Mandelbrot
{

	function Mandelbrot()
	{
		$d1 = microtime(1);
		for ($y = -39; $y < 39; $y++) {
			echo("\n");
			for ($x = -39; $x < 39; $x++) {
				if ($this->iterate($x/40.0,$y/40.0) == 0)
					echo("*");
				else
					echo(" ");

			}
		}
		$d2 = microtime(1);
		$diff = $d2 - $d1;
		printf("\nPHP Elapsed %0.2f", $diff);
	}

	function iterate($x,$y)
	{
		$cr = $y-0.5;
		$ci = $x;
		$zi = 0.0;
		$zr = 0.0;
		$i = 0;
		while (true) {
			$i++;
			$temp = $zr * $zi;
			$zr2 = $zr * $zr;
			$zi2 = $zi * $zi;
			$zr = $zr2 - $zi2 + $cr;
			$zi = $temp + $temp + $ci;
			if ($zi2 + $zr2 > BAILOUT)
				return $i;
			if ($i > MAX_ITERATIONS)
				return 0;
		}

	}

}

$m = new Mandelbrot();
?>