Group associative array data by key prefix - php

Question

I have a array like this
Array (
[operator_15] => 3
[fiter_15] => 4
[operator_17] => 5
[fiter_17] => 5
[operator_19] => 4
[fiter_19] => 2
)
I want to separate this array in to 2 arrays:
key starting from fiter_
key starting from operator_
I used array filter and it doesn't work. any other option?
$array = array_filter(
$fitered_values,
function($key) {
return strpos($key, 'fiter_') === 0;
}
);

Answer 1

Just loop the array and substring what is before the _ with strpos and substr then you can filter them to a new array as this.
This method will also work with new array keys, see example:
$arr = array ( "operator_15" => 3,
"fiter_15" => 4,
"operator_17" => 5,
"fiter_17" => 5,
"somethingelse_12" => 99 // <--- Notice this line.
);
foreach($arr as $key => $val){
$subarr = substr($key,0, strpos($key, "_"));
$new[$subarr][$key] = $val;
}
var_dump($new);
output:
array(3) {
["operator"]=>
array(2) {
["operator_15"]=>
int(3)
["operator_17"]=>
int(5)
}
["fiter"]=>
array(2) {
["fiter_15"]=>
int(4)
["fiter_17"]=>
int(5)
}
["somethingelse"]=> // <-- is here now in it's own group with no code added
array(1) {
["somethingelse_12"]=>
int(99)
}
}

Answer 2

Give a try with below and see if its solve your problem
$array = array (
'operator_15' => 3,
'fiter_15' => 4,
'operator_17' => 5,
'fiter_17' => 5,
'operator_19' => 4,
'fiter_19' => 2 );
$operator=array();
$filter=array();
foreach($array as $key => $value){
if (strpos($key, 'operator_') !== false) {
$operator[$key] = $value;
}
if (strpos($key, 'fiter_') !== false) {
$filter[$key] = $value;
}
}
print_r($operator);
print_r($filter);

Answer 3

While iterating your array, populate a new array with first level (grouping) keys based on the prefix (substring before the underscore), then push the original associative data into that group.
Code: (Demo)
$result = [];
foreach ($array as $k => $v) {
$result[strtok($k, '_')][$k] = $v;
}
var_export($result);
It is suboptimal programming to declare individual variables because this removes the convenience of being able to easily iterate related data (related by structure).
The above snippet will allow you to iterate $result and access all data sets or you can individually access a particular subset like $result['fiter'].

Answer 4

This is a working example:
$a = array ( 'operator_15' => 3, 'fiter_15' => 4, 'operator_17' => 5, 'fiter_17' => 5, 'operator_19' => 4, 'fiter_19' => 2 );
$fiter_array = array();
$operator_array = array();
foreach($a as $key => $val)
{
if(strpos($key, 'fiter') !== false)
{
array_push($fiter_array, $a[$key]);
// or if you want to maintain the key
$fiter_array[$key] = $val;
}
else
{
array_push($operator_array, $a[$key]);
// or if you want to maintain the key
$operator_array[$key] = $val;
}
};
var_dump($fiter_array);
var_dump($operator_array);