PHP Ds Vector reduce()用法及代码示例

Ds\Vector::reduce() 函数可以使用回调函数将向量减少到单个值。

用法

public mixed Ds\Vector::reduce( callable $callback [, mixed $initial ] )

Ds\Vector::reduce() 函数可以返回最终回调的值。

例子1

<?php 
   $vector = new \Ds\Vector([1, 2, 3, 4, 5]); 
   
   echo("The original vector elements:\n"); 
   print_r($vector); 
   
   echo("\n The element after performing operation:\n"); 
   var_dump($vector->reduce(function($carry, $element) { 
      return $carry + $element + 2; 
   })); 
?>

例子2

<?php 
   $vector = new \Ds\Vector([10, 20, 30, 40, 50]); 
   
   echo("The original vector elements:\n"); 
   print_r($vector); 
  
   $func = function($carry, $element) { 
      return $carry * $element; 
   }; 
   
   echo("\n The vector after reducing to single element:\n"); 
   var_dump($vect->reduce($func, 10)); 
?>