array_map() function in PHP

The array_map() function sends each value of an array to a user-made function, which returns new values.

Syntax

array_map(callback, arr1, arr2 −, arr3 −, arr4 −, …)

Parameters

• callback− The callback function

• arr1 − The array to be modified

• arr2 − The array to be modified

• arr3 − The array to be modified

Return

The array_map() function returns an array containing the values of the first array, after applying the user-made function to each one.

Example

<?php
function square($n) {
   return($n * $n);
}
$arr = array(1, 2, 3);
$res = array_map("square", $arr);
print_r($res);
?>

Output

Array
(
[0] => 1
[1] => 4
[2] => 9
)

Example

Let us see another example to create array of arrays using array_map().

<?php
$arr1 = array(1, 2, 3);
$arr2 = array("steve", "david", "nadal");
$arr3 = array("cricket", "football", "tennis");
$res = array_map(null, $arr1, $arr2, $arr3);
print_r($res);
?>

Output

Array
(
[0] => Array
(
[0] => 1
[1] => steve
[2] => cricket
)

[1] => Array
(
[0] => 2
[1] => david
[2] => football
)

[2] => Array
(
[0] => 3
[1] => nadal
[2] => tennis
)
)