使用php-timeit估计php函数的执行时间_php实例

/**
 * Compute the delay to execute a function a number of time
 * @param $count Number of time that the tests will execute the given function
 * @param $function  the function to test. Can be a string with parameters (ex: 'myfunc(123, 0, 342)') or a callback
 * @return float   Duration in seconds (as a float)
 */
function timeit($count, $function) {
 if ($count 

//取平方根
function sqrt_nd($num){
 $value = $num;
 while(abs($value*$value -$num) > 0.001){
  $value = ($value + $num/$value)/2;
 }
 return $value;
}
print timeit(1000, 'sqrt_nd(5)');
print "\n";
print timeit(1000, 'sqrt(5)');

';
}
$end_time = microtime(true);