PHP sum by other field from unique id in array - php

Question

I have an multidimensional array like this one:
Array
(
[0] => array('id'=>1,'name'=>'Agent 1','total'=>3)
[1] => array('id'=>2,'name'=>'Agent 2','total'=>3)
[2] => array('id'=>3,'name'=>'Agent 3','total'=>3)
[3] => array('id'=>1,'name'=>'Agent 1','total'=>6)
)
And I want to remove duplicate agents from this array and sum the total field to end up in a array like this:
Array
(
[0] => array('id'=>1,'name'=>'Agent 1','total'=>9)
[1] => array('id'=>2,'name'=>'Agent 2','total'=>3)
[2] => array('id'=>3,'name'=>'Agent 3','total'=>3)
)
I have tried array_unique but it only remove duplicates...

Answer 1

Try this code: sandbox code
Main idea of algorithm - caching key pairs in result array and further checking existence of them.
$array = [
0 => ['id' => 1, 'name' => 'Agent 1', 'total' => 3],
1 => ['id' => 2, 'name' => 'Agent 2', 'total' => 3],
2 => ['id' => 3, 'name' => 'Agent 3', 'total' => 3],
3 => ['id' => 1, 'name' => 'Agent 1', 'total' => 6],
];
$sumArray = [];
foreach ($array as $agentInfo) {
// create new item in result array if pair 'id'+'name' not exists
if (!isset($sumArray[$agentInfo['id'].$agentInfo['name']])) {
$sumArray[$agentInfo['id'].$agentInfo['name']] = $agentInfo;
} else {
// apply sum to existing element otherwise
$sumArray[$agentInfo['id'].$agentInfo['name']]['total'] += $agentInfo['total'];
}
}
// optional action to flush keys of array
$sumArray = array_values($sumArray);
print_r ($sumArray);

Answer 2

Try this,
$arrays = array_values(array_combine(array_map(function ($i) { return $i['id']; }, $array), $array));
print_r($arrays);
DEMO

Answer 3

assuming an id is unique you could use this
$array = array(
array('id' => 1, 'name' => 'Agent 1', 'total' => 3),
array('id' => 2, 'name' => 'Agent 2', 'total' => 3),
array('id' => 3, 'name' => 'Agent 3', 'total' => 3),
array('id' => 1, 'name' => 'Agent 1', 'total' => 6)
);
$array_ids = array();
foreach ($array as $key => $value) {
if (isset($array_ids[$value['id']])) {
$array[$array_ids[$value['id']]]['total'] += $value['total'];
unset($array[$key]);
}
else
{
$array_ids[$value['id']] = $key;
}
}
in this way you save the used id's into array $array_ids, with that you can easily check if an agent already exists in the array

Answer 4

In order to achieve the exact output you desire, you will need a nested loop.
$input = array(
0 => array('id'=>1,'name'=>'Agent 1','total'=>3),
1 => array('id'=>2,'name'=>'Agent 2','total'=>3),
2 => array('id'=>3,'name'=>'Agent 3','total'=>3),
3 => array('id'=>1,'name'=>'Agent 1','total'=>6)
);
// This is where we will save our result
$output = array();
foreach ($input as $item) {
// Used to determine if the current $item
// already exists in the $output array
$foundItem = false;
// Now we check the $item against every output entry
foreach ($output as &$entry) {
if ($entry["id"] == $item["id"]) {
// Since we found a match, let's add the
//current item's total to the output total.
$entry["total"] += $item["total"];
// Marking this as true will later prevent us
// from inserting the item to the output array twice
$foundItem = true;
}
}
// If the item was not found in the output array
// the $foundItem variable remains false
// Using ! to negate the boolean, we insert the item to the output array
if (!$foundItem) {
$output[] = $item;
}
}
Realize that this is not the only way to get the required output. This only is the simplest solution and can certainly be improved in many ways. However, I will leave that part up to you.

Answer 5

I have tried using array_reduce - Iteratively reduce the array to a single value using a callback function. And written a function according to the requirements. Hope this will help you.
<?php
$array = [
0 => ['id' => 1, 'name' => 'Agent 1', 'total' => 3],
1 => ['id' => 2, 'name' => 'Agent 2', 'total' => 3],
2 => ['id' => 3, 'name' => 'Agent 3', 'total' => 3],
3 => ['id' => 1, 'name' => 'Agent 1', 'total' => 6],
];
$result = array_reduce($array, function($temp, $item){
isset($temp[$item['id']])
? $temp[$item['id']]['total'] += $item['total']
: $temp[$item['id']] = $item;
return $temp;
}, []);
print_r($result);
?>
OUTPUT
Array
(
[1] => Array ( [id] => 1 [name] => Agent 1 [total] => 9 )
[2] => Array ( [id] => 2 [name] => Agent 2 [total] => 3 )
[3] => Array ( [id] => 3 [name] => Agent 3 [total] => 3 )
)