sum values with given key in php? [duplicate] - php

Question

This question already has answers here:
How to GROUP BY and SUM PHP Array? [duplicate]
(2 answers)
Closed 5 months ago.
given this array:
array(40) {
[0]=>
array(10) {
["item"]=>
string(5) "AABBCC"
["quants"]=>
string(1) "1"
}
[1]=>
array(10) {
["item"]=>
string(5) "AABBCC"
["quants"]=>
string(1) "1"
}
[2]=>
array(10) {
["item"]=>
string(5) "SLF02"
["quants"]=>
string(1) "1"
}
[3]=>
array(10) {
["item"]=>
string(5) "SLF02"
["quants"]=>
string(1) "3"
}
}
how without using a foreach do I end up with this output:
array(40) {
[0]=>
array(10) {
["item"]=>
string(5) "AABBCC"
["quants"]=>
string(1) "2"
}
[1]=>
array(10) {
["item"]=>
string(5) "SLF02"
["quants"]=>
string(1) "3"
}
}
are there any array_sum functions to do this with a multidimensional array like this in php?

Answer 1

This is a bad idea, but seemed like a fun challenge to do without a foreach:
$arr =
[
[
"item" =>"AABBCC",
"quants" => "1",
],
[
"item" => "AABBCC",
"quants" => "1",
],
[
"item" => "SLF02",
"quants" => "1",
],
[
"item" => "SLF02",
"quants" => "3",
]
];
$arr = array_values(call_user_func_array("array_merge", array_map(function($i) use ($arr) {
return [$i["item"] => ["item" => $i["item"], "quants" => array_reduce(
array_filter($arr, function($j) use ($i) {
return $j["item"] == $i["item"];
}), function($carry, $item) {
return $carry + $item["quants"];
})
]];
}, $arr)));
var_dump($arr);
/*
array(2) {
[0]=>
array(2) {
["item"]=>
string(6) "AABBCC"
["quants"]=>
int(2)
}
[1]=>
array(2) {
["item"]=>
string(5) "SLF02"
["quants"]=>
int(4)
}
}
*/

Answer 2

Here's my approach:
<?php
$array = array(
array('item'=>'AABBCC','quants'=>1),
array('item'=>'AABBCC','quants'=>1),
array('item'=>'SLF02','quants'=>1),
array('item'=>'SLF02','quants'=>3),
);
$summed_array = array();
foreach($array as $row){
$key = $row['item'];
if(!isset($summed_array[$key])){
$summed_array[$key] = array(
'item' => $row['item'],
'quants' => 0
);
}
$summed_array[$key]['quants'] += $row['quants'];
}
// turn the array back to a 0 based array
$summed_array = array_values($summed_array);
echo '<pre>',print_r($summed_array),'</pre>';