Group 2d array data using column value to create a 3d array - php

Question

I have a multidimensional array and am trying to group them according to the value in a specific column.
I'm trying to group them by level, but I won't actually know the level beforehand. So, it's not like I can put it in a for loop and say while $i < 7, because I won't know that 7 is the maximum value for the level key, and frankly, I'm not sure that's how I would need to do it even if I did.
[
['cust' => 'XT8900', 'type' => 'standard', 'level' => 1],
['cust' => 'XT8944', 'type' => 'standard', 'level' => 1],
['cust' => 'XT8922', 'type' => 'premier', 'level' => 3],
['cust' => 'XT8816', 'type' => 'permier', 'level' => 3],
['cust' => 'XT7434', 'type' => 'standard', 'level' => 7],
]
Desired result:
Array (
[1] => Array (
[0] => Array (
[cust] => XT8900
[type] => standard
)
[1] => Array (
[cust] => XT8944
[type] => standard
)
)
[3] => Array (
[2] => Array (
[cust] => XT8922
[type] => premier
)
[3] => Array (
[cust] => XT8816
[type] => permier
)
)
[7] => Array (
[4] => Array (
[cust] => XT7434
[type] => standard
)
)
)

Answer 1

Best way, if you have control over building the initial array, is just set things up like that at the start as you add entries.
If not then build a temporary array to sort:
foreach ($input_arr as $key => &$entry) {
$level_arr[$entry['level']][$key] = $entry;
}
Leaves you with the form you wanted and everything referenced together.
Build the array like that in the first place though if at all possible.

Answer 2

You need to group them by level first
Use foreach to loop into array check if the level is the same with the previous item then group it with that array
$templevel=0;
$newkey=0;
$grouparr[$templevel]="";
foreach ($items as $key => $val) {
if ($templevel==$val['level']){
$grouparr[$templevel][$newkey]=$val;
} else {
$grouparr[$val['level']][$newkey]=$val;
}
$newkey++;
}
print($grouparr);
The output of print($grouparr); will display like the format you hoped for
You can also try to
print($grouparr[7]);
Will display
[7] => Array (
[4] => Array (
[cust] => XT7434
[type] => standard
)
)
Or
print($grouparr[3]);
Will display
[3] => Array (
[2] => Array (
[cust] => XT8922
[type] => premier
)
[3] => Array (
[cust] => XT8816
[type] => permier
)
)

Answer 3

Here is the solution I landed on for an identical problem, wrapped as a function:
function arraySort($input,$sortkey){
foreach ($input as $key=>$val) $output[$val[$sortkey]][]=$val;
return $output;
}
To sort $myarray by the key named "level" just do this:
$myArray = arraySort($myArray,'level');
Or if you didn't want it as a function, just for a one time use, this would create $myNewArray from $myArray grouped by the key 'level'
foreach ($myArray as $key=>$val) $myNewArray[$val['level']][]=$val;

Answer 4

function group_assoc($array, $key) {
$return = array();
foreach($array as $v) {
$return[$v[$key]][] = $v;
}
return $return;
}
//Group the requests by their account_id
$account_requests = group_assoc($requests, 'account_id');

Answer 5

$result = array();
foreach ($yourArrayList as $data) {
$id = $data['level'];
if (isset($result[$id])) {
$result[$id][] = $data;
} else {
$result[$id] = array($data);
}
}

Answer 6

Best ans.
$levels = array_unique(array_column($records, 'level'));
$data = array();
foreach($records as $key => $value){
$data[$levels[array_search($value['level'],$levels )]][] = $value ;
}
print_r($data);

Answer 7

To generate the question's exact desured output from the sample input, pull/pop the last value from each row, use that value as the first level grouping key. Then use the original first level index as the second level key. Then push the two remaining elements into the group's subset.
Code: (Demo)
$result = [];
foreach ($array as $key => $row) {
$result[array_pop($row)][$key] = $row;
}
var_export($result);
For functional style syntax, use array_reduce(). (Demo)
var_export(
array_reduce(
array_keys($array),
function($result, $key) use ($array) {
$result[array_pop($array[$key])][$key] = $array[$key];
return $result;
}
)
);

Answer 8

function _group_by($array,$key,$keyName)
{
$return = array();
foreach($array as $val) {
$return[$keyName.$val[$key]][] = $val;
}
return $return;
} //end of function