How to create dynamic array using existing array - php

Question

I have on array of data in below.
Array
(
[0] => Array
(
[0] => Array
(
[rating] => 4
[review] => nice
)
[1] => Array
(
[rating] => 2
[review] => good
)
)
)
We customize above array and need to my custom array .
Need out put like below array. array always need 5 to 1 key because i am using this array for rating & review functionality.
Array
(
[0] => Array
(
[5] => Array
(
[rating] => 0
[review] => ""
)
[4] => Array
(
[rating] => 4
[review] => nice
)
[3] => Array
(
[rating] => 0
[review] => ""
)
[2] => Array
(
[rating] => 2
[review] => "good"
)
[1] => Array
(
[rating] => 0
[review] => ""
)
)
)

Answer 1

I managed to self-solve. Please find below solution as per output.
$arr1 = array(array("rating"=>4,"review"=>"nice"),array("rating"=>2,"review"=>"good"));
$final =a rray();
for ($i=5; $i>=1; $i--) {
foreach ($arr1 as $key =>$val) {
if ($val['rating']==$i) {
$final[$i] = array("rating"=>$val['rating'],"review"=>$val['review']);
break;
} else {
$final[$i] = array("rating"=>0,"review"=>"");
}
}
}
print_r($final);

Answer 2

Iterate each top level array (if you don't have multiple top level arrays, then you should consider restructuring your array structure to be more concise)
call array_column() on the level2 array so that the rating values are assigned as keys for their respective subarray.
Iterate in descending order from 5 to 1 while conditionally saving data to the output array.
Code: (Demo)
$input = [
[
['rating' => 4, 'review' => 'nice'],
['rating' => 2, 'review' => 'good']
]
];
foreach ($input as $x => $level2) {
$keyed = array_column($level2, null, 'rating'); // setup more efficient lookup
for($i = 5 ; $i > 0 ; --$i) {
$result[$x][$i] = isset($keyed[$i]) ? $keyed[$i] : ['rating' => 0, 'review' => ''];
}
}
var_export($result);
// output is as desired