Counting an eliminating duplicate associative values in an array - php

Question

I have the following issue, I have an array with the name $data
Within this array I have something like
[6] => Array
(
[code] => 642
[total] => 1708
)
[7] => Array
(
[code] => 642
[total] => 53
)
[8] => Array
(
[code] => 642
[total] => 1421
)
In some elements the code value is the same, now what I want to do is merge all the elements with the same code value together, and adding the totals together. I tried doing this in a foreach loop, but does not seem to work.
I do something like this
$old_lc = null;
$old_lcv = 0;
$count = 0;
$dd = null;
foreach($data as $d){
if($d['code'] == $old_lc){
$d['total'] = $d['total'] + $old_lcv;
$count--;
$dd[$count]['code'] = $d['code'];
$dd[$count]['total'] = $d['total'];
}else{
$dd[$count]['code'] = $d['code'];
$dd[$count]['total'] = $d['total'];
$count++;
}
$old_lc = $d['code'];
$old_lcv = $d['total'];
}
$data = $dd;
But this does not seem to work. Also I need the $data array to keep the keys, and should remain in the same format

Answer 1

$result = array();
foreach($ary as $elem) {
$code = $elem['code'];
$total = $elem['total'];
if(!isset($result[$code]))
$result[$code] = 0;
$result[$code] += $total;
}

Answer 2

This code translates the above array into an array of code => total.
$out = array();
foreach ($data as $k => $v) {
$out[$v['code']] += $v['total'];
}
It is worth noting that on certain settings this will generate a warning about undefined indexes. If this bothers you, you can use this alternate version:
$out = array();
foreach ($data as $k => $v) {
if (array_key_exists($v['code'], $out)) {
$out[$v['code']] += $v['total'];
} else {
$out[$v['code']] = $v['code'];
}
}
This turns it back into something like the original, if that's what you want:
$output = array();
foreach ($out as $code => $total) {
$output[] = array('code' => $code, 'total' => $total);
}
Note: the original keys of $data aren't maintained but it wasn't stated that this was a requirement. If it is, it needs to be specified how to reconstruct multiple elements that have the same code.

Answer 3

[6] => Array
(
[code] => 642
[total] => 1708
)
[7] => Array
(
[code] => 642
[total] => 53
)
[8] => Array
(
[code] => 642
[total] => 1421
)
$data_rec = array();
$data = array();
foreach($data_rec as $key=>$rec)
{
$data[$key]+= $rec[$key];
}
print_r($data);