Converting Block of code Into Function

Question

I have those few lines of code:

        $array_to_filter // this array is unfiltered

   array_filter($array_to_filter, function($v){return array_filter($v) == array();});
    $c = function($v){
    return array_filter($v) != array();
    };
    $filtered_array = array_filter($airbnb, $c);


    print_r($filtered_array); // this is filtered array!

Now I will be using this piece of code alot in my code and I don't want to repeat it every time! I have tried to do this:

    function filter_array ($tofilter, $filtered) {

    array_filter($tofilter, function($v){return array_filter($v) == array();});
    $c = function($v){
    return array_filter($v) != array();
    };
    $filtered = array_filter($filtered, $c); 
    return $filtered;
}

And calling it like this: filter_array($array_to_filter, $filtered_array);

Without any luck.. What am I doing wrong?

The array I want to filter:

    [0] => Array
    (
        [RES_ID] => 2927135
        [CONFIRMATION] =>  QBMNMA
        [AIRBNB_AGENCY_INCOME] =>  €497
        [AIRBNB_INCOME] =>  €516

        [AIRBNB_FEES] =>  -€19

        [AIRBNB_PER_NIGHT] =>  €129
    )

[1] => Array
    (
        [RES_ID] => 
        [CONFIRMATION] => 
        [AIRBNB_AGENCY_INCOME] => 
        [AIRBNB_INCOME] => 
        [AIRBNB_FEES] => 
        [AIRBNB_PER_NIGHT] => 
    )

The result via the block of code:

 [0] => Array
    (
        [RES_ID] => 2927135
        [CONFIRMATION] =>  QBMNMA
        [AIRBNB_AGENCY_INCOME] =>  €497
        [AIRBNB_INCOME] =>  €516

        [AIRBNB_FEES] =>  -€19

        [AIRBNB_PER_NIGHT] =>  €129
    )

The result via the function:

<p>Severity: Warning</p>
<p>Message:  array_filter() expects parameter 1 to be array, null given</p>
<p>Filename: controllers/Welcome.php</p>
<p>Line Number: 456</p>

Answer 1

I have an Associative array but some of the arrays are empty! inside for example the [RES_ID] => I want to get rid of this whole array not just the key. that's what it does – Valery 5 mins ago

function filter_array ($to_filter)
{
    foreach ($to_filter as $index => $child_array)
    {
        if (!array_filter($child_array)) {
            // all keys are empty.
            unset($to_filter[$index]);
        }
    }

return $to_filter;
}

$filtered_array = filter_array($array_to_filter);

Would this work?