PHP array_reduce() Function (original) (raw)

Last Updated : 20 Jun, 2023

This inbuilt function of PHP is used to reduce the elements of an array into a single value that can be of float, integer or string value. The function uses a user-defined callback function to reduce the input array.

Syntax:

array_reduce($array, own_function, $initial)

Parameters:
The function takes three arguments and are described below:

  1. $array (mandatory): This is a mandatory parameter and refers to the original array from which we need to reduce.
  2. own_function (mandatory): This parameter is also mandatory and refers to the user-defined function that is used to hold the value of the $array
  3. $initial (optional): This parameter is optional and refers to the value to be sent to the function.

Return Value: This function returns the reduced result. It can be of any type int, float or string.

Examples:

Input : $array = (15, 120, 45, 78) $initial = 25 own_function() takes two parameters and concatenates them with "and" as a separator in between Output : 25 and 15 and 120 and 45 and 78

Input : $array = array(2, 4, 5); $initial = 1 own_function() takes two parameters and multiplies them. Output : 40

In this program, we will see how an array of integer elements is reduced to a single string value. We also passed the initial element of our choice.

PHP `

element1."and".element1 . " and " . element1."and".element2; } $array = array(15, 120, 45, 78); print_r(array_reduce($array, "own_function", "Initial")); ?>

`

Output:

Initial and 15 and 120 and 45 and 78

In the below program, the array_reduce reduces the given array to the product of all the elements of the array using the own_function().

PHP `

element1=element1 = element1=element1 * $element2; return $element1; } $array = array(2, 4, 5, 10, 100); print_r(array_reduce($array, "own_function", "2")); ?>

`

Output:

80000

Reference:
http://php.net/manual/en/function.array-reduce.php