Addition of php associative array values not working - php

Question

Trying to add a bunch of array values together, keeping the ID value....
I thought I could use a basic foreach with a += operator, but it's not working out.
Here are my arrays:
Array(
[0] => Array(
[246] => Array(
[amount] => 2
)
)
)
Array(
[0] => Array(
[245] => Array(
[amount] => 1
)
)
)
Array(
[0] => Array(
[243] => Array(
[amount] => 2
)
)
)
Array(
[0] => Array(
[245] => Array(
[amount] => 1
)
)
)
Array(
[0] => Array(
[243] => Array(
[amount] => 2
)
)
)
What I'm trying to get is:
array(
'243' => '4',
'245' => '2',
'246' => '2',
);
And here's what I was attempting:
$sumArray = array();
foreach ($orgArray[0] as $k=>$subArray) {
foreach ($subArray as $id=>$value) {
$sumArray[$k]+=$value;
}
}
Here is what I'm getting:
Array
(
[243] => 2
)

Answer 1

You simply need to modify your foreach loops as you're trying to set $key which is the index of the arrays which for the example above would be 0,1,2,3...etc not 246,245,243...etc as you expect.
This is what you want.
$orgArray = [
[246 => ['amount' => 2]],
[245 => ['amount' => 1]],
[243 => ['amount' => 2]],
[245 => ['amount' => 1]],
[243 => ['amount' => 2]],
];
$sumArray = array();
foreach ($orgArray as $k => $subArray) {
foreach ($subArray as $id => $item) {
if (!isset($sumArray[$id])) {
$sumArray[$id] = 0;
}
$sumArray[$id] += $item['amount'];
}
}
Note: The above [] array identifier is assuming you're using the correct php version that allows it, otherwise you'd have to change them to array()
Which returns:
Array
(
[246] => 2
[245] => 2
[243] => 4
)
As expected.
EXAMPLE