array_unique in php with subarray in array

Question

How can i use array_unique function for this array `

$mon  = array('9:00AM - 11:00AM','1:00pm-6pm');
$tue  = array('8:00AM - 11:00AM','12:00pm-6pm');
$wed  = array('9:00AM - 11:00AM','1:00pm-6pm');
$thu  = array('9:00AM - 11:00AM','1:00pm-6pm');
$fri  = array('9:00AM - 12:00PM','1:00pm-6pm');
$sat  = array('9:00AM - 7:00PM');
$sun  = array('9:00AM - 12:00AM','1:00pm-6pm');

$a=array($mon , $tue , $wed , $thu , $fri , $sat , $sun);
print_r(array_unique($a));

@Lino The irony of linking to a German edition of the manual and cursing "read the $#@$@#$ manual" amuses me. — Ultimater, Dec 15 '15 at 07:49
@Ultimater oh, i always forget that this stupid man page is geo located :-) — Lino, Dec 15 '15 at 07:51

Sanjay · Answer 1 · 2015-12-15T07:56:06.847

You have to write custom function for multi dimensional array, please refer below function

function unique_multidim_array($array, $key){
$temp_array = array();
$i = 0;
$key_array = array();

foreach($array as $val){
    if(!in_array($val[$key],$key_array)){
        $key_array[$i] = $val[$key];
        $temp_array[$i] = $val;
    }
    $i++;
}
return $temp_array; }

Now, call this function anywhere from your code

 $details = unique_multidim_array($details,'id');

if your case you have to pass key as 0 or 1 like

$a=unique_multidim_array($a,0);

score 1 · Accepted Answer · answered Dec 15 '15 at 08:14

You may use this solution also:

$schedule = array(
    array('9:00AM - 11:00AM','1:00pm-6pm'),
    array('8:00AM - 11:00AM','12:00pm-6pm'),
    array('9:00AM - 11:00AM','1:00pm-6pm'),
    array('9:00AM - 11:00AM','1:00pm-6pm'),
    array('9:00AM - 12:00PM','1:00pm-6pm'),
    array('9:00AM - 7:00PM'),
    array('9:00AM - 12:00AM','1:00pm-6pm'),
);

$schedule = array_map(function ($item) {
    return json_encode($item);
}, $schedule);

// use array_flip to switch keys and values. By doing it the duplicates will be removed    
$json = '[' . implode(',', array_keys(array_flip($schedule))) . ']';
$schedule = json_decode($json);

var_dump($schedule);

score 0 · Answer 3 · answered Sep 02 '20 at 12:03

For array_unique(), the PHP manual PHP manual says

Two elements are considered equal if and only if (string) $elem1 === (string) $elem2 i.e. when the string representation is the same, the first element will be used

So internally, each element of the input array is cast to string before comparison. When you have subarrays as elements, casting them to string will output an "Array to string conversion" notice and return a useless result:

var_dump((string)['foo', 'bar']); // string(5) "Array"

Fortunately, building a replacement for array_unique() is easy:

function uniquify(array $arr) {
    return array_reduce(
        $arr,
        function ($carry, $item) {
            if (!in_array($item, $carry)) {
                $carry[] = $item;
            }
            return $carry;
        },
        []
    );
}

array_unique in php with subarray in array

3 Answers3