PHP array_reduce() Function Last Updated : 20 Jun, 2023 Comments Improve Suggest changes Like Article Like Report 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: $array (mandatory): This is a mandatory parameter and refers to the original array from which we need to reduce.own_function (mandatory): This parameter is also mandatory and refers to the user-defined function that is used to hold the value of the $array$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); $initial = 1 own_function() takes two parameters and multiplies them. Output : 40 In this program, we will see how an array of integer elements is reduced to a single string value. We also passed the initial element of our choice. PHP // PHP function to illustrate the use of array_reduce() function own_function($element1, $element2) { return $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 // PHP function to illustrate the use of array_reduce() function own_function($element1, $element2) { $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 Comment More infoAdvertise with us Next Article PHP array_reduce() Function chinmoy lenka Follow Improve Article Tags : Misc Web Technologies PHP PHP-array PHP-function +1 More Practice Tags : Misc Similar Reads PHP array_chunk() Function The array_chunk() function is an inbuilt function in PHP which is used to split an array into parts or chunks of given size depending upon the parameters passed to the function. The last chunk may contain fewer elements than the desired size of the chunk. 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