Array Helper

The Array helper assists in transforming arrays. Warning, in order to use it, class name is 'arr' instead of 'array'.

'rotate' rotates an array (two-dimensional) matrix clockwise. Example, turns a 2×3 array into a 3×2 array.

The two arguments are:

• [array] The array you want to rotate
• [boolean] Do you want to keep the same keys in the rotated array? – TRUE by default

Example:

// Please note that the print() statements are for display only
$optical_discs = array
			(
				'CD'  => array('700', '780'),
				'DVD' => array('4700','650'),
				'BD' => array('25000','405')
			);
print Kohana::debug($optical_discs);
$optical_discs = arr::rotate($optical_discs, FALSE);
print ('<br /><br />');
print Kohana::debug($optical_discs);

It will result in HTML as:

Array
(
    [CD] => Array
        (
            [0] => 700
            [1] => 780
        )
 
    [DVD] => Array
        (
            [0] => 4700
            [1] => 650
        )
 
    [BD] => Array
        (
            [0] => 25000
            [1] => 405
        )
 
)
 
 
Array
(
    [0] => Array
        (
            [CD] => 700
            [DVD] => 4700
            [BD] => 25000
        )
 
    [1] => Array
        (
            [CD] => 780
            [DVD] => 650
            [BD] => 405
        )
 
)

'remove' removes a key from an array and returns it.

The two arguments are:

• [string] The key you want removed from an array
• [array] The array you want the key to be removed from

Example:

// Please note that the print() statements are for display only
$optical_discs = array
			(
				'CD'  => array('700', '780'),
				'DVD' => array('4700','650'),
				'BD' => array('25000','405')
			);
print Kohana::debug($optical_discs);
$cd = arr::remove('CD', $optical_discs);
print ('<br />');
print Kohana::debug($cd);
print ('<br />');
print Kohana::debug($optical_discs);

It will result in HTML as:

Array
(
    [CD] => Array
        (
            [0] => 700
            [1] => 780
        )
 
    [DVD] => Array
        (
            [0] => 4700
            [1] => 650
        )
 
    [BD] => Array
        (
            [0] => 25000
            [1] => 405
        )
 
)
 
 
Array
(
    [0] => 700
    [1] => 780
)
 
 
Array
(
    [DVD] => Array
        (
            [0] => 4700
            [1] => 650
        )
 
    [BD] => Array
        (
            [0] => 25000
            [1] => 405
        )
 
)

'extract' extract ones or more keys from an array. Keys that do not exist in the search array will be NULL in the extracted data.

The two arguments are:

• [array] The array you want the key to be extracted from
• [string] The key you want extracted from an array

Example:

 $optical_discs = array
			(
				'CD'  => array('700', '780'),
				'DVD' => array('4700','650'),
				'BD' => array('25000','405')
			);
$optical_discs = arr::extract($optical_discs, 'DVD', 'Bluray');
echo Kohana::debug($optical_discs);

Output:

(array) Array
(
    [DVD] => Array
        (
            [0] => 4700
            [1] => 650
        )
 
    [Bluray] =>  //NULL
)

'binary_search' performs a basic binary search on an array. By default, it returns the key of the array value it finds. The four arguments are:

• [mixed] The value you want to find.
• [array] The sorted array you want to search in
• [boolean] Return the nearest value, or simply return FALSE (the default)
• [boolean] Sort the array before searching

Example:

$my_array = array('10', '20', '30', '50', '80');
echo arr::binary_search('50', $my_array);
// 3
 
echo arr::binary_search('45', $my_array);
// FALSE (not found)
 
echo arr::binary_search('45', $my_array, TRUE);
// 3
 
echo arr::binary_search('35', $my_array, TRUE);
// 2

'range' fills an array with a range of numbers.

The two arguments are:

• [integer] Stepping
• [integer] Ending Number

Example:

echo Kohana::debug(arr::range(17, 150));

Output:

(array) Array
(
    [17] => 17
    [34] => 34
    [51] => 51
    [68] => 68
    [85] => 85
    [102] => 102
    [119] => 119
    [136] => 136
)

Emulates array_merge_recursive, but appends numeric keys and replaces associative keys, instead of appending all keys. It takes:

• [array] any number of arrays
• returns [array] the merged array

Example:

echo Kohana::debug(arr::merge(array('a', 'b'), array('c', 'd'), array('e' => array('f', 'g'))));

It will result as:

(array) Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [e] => Array
        (
            [0] => f
            [1] => g
        )
 
)

'overwrite' overwrites an array with values from input array(s). Note that non-existing keys will not be appended. It takes:

• [array] key array
• [array] input array(s) that will overwrite key array values

Example:

$array1 = array('fruit1' => 'apple', 'fruit2' => 'mango', 'fruit3' => 'pineapple');
$array2 = array('fruit1' => 'strawberry', 'fruit4' => 'coconut');
print Kohana::debug(arr::overwrite($array1, $array2));

Output:

(array) Array
(
    [fruit1] => strawberry
    [fruit2] => mango
    [fruit3] => pineapple
)

map_recursive($callback, array $array) has been created because PHP does not have this function, and array_walk_recursive creates references in arrays and is not truly recursive. It takes:

• [array] $callback a valid callback to apply to each member of the array
• [array] $array array to map to
• returns [array] the mapped array

Example :

public function add($value){
    return $value + 1;
}
 
echo Kohana::debug(arr::map_recursive(array($this, 'add'), array('a' => 1, 'b' => 2, 'c' => array(3, 4), 'd' => array('e' => 5))));

It will result as:

(array) Array
(
    [a] => 2
    [b] => 3
    [c] => Array
        (
            [0] => 4
            [1] => 5
        )
 
    [d] => Array
        (
            [e] => 6
        )
)

unshift_assoc has been created because PHP does not have this function. It just unshift an association in an associative array. It takes:

• [array] array to unshift
• [string] key to unshift
• [mixed] value to unshift

Example

$fruits = array('fruit1' => 'apple', 'fruit2' => 'mango', 'fruit3' => 'pineapple');
arr::unshift_assoc($fruits, 'fruit1', 'strawberry');
print Kohana::debug($fruits);

Output

(array) Array
(
    [fruit1] => strawberry
    [fruit2] => mango
    [fruit3] => pineapple
)

to_object(array $array, $class = 'stdClass') converts an array to an object. This method supports multi level arrays. It takes:

• [array] $array array to convert
• [string] $class the base class (default 'stdClass')

Note: For 1-level arrays, use Typecasting $object = (object) $array;

Example

$array = arr::to_object(array('test' => 13));
print $array ->test;
print Kohana::debug($array);

Output

13
(object) stdClass Object
(
    [test] => 13
)