[RESOLVED] This should be a simple array_sum but it isn't

[gwerner]

I have a foreach loop that is running for each product in a particular product category. Inside this loop I am generating the total cost of inventory. I would like to sum arrays together that have the same key index. Is this possible? I'm not figuring out a solution.

Below is what is being output if I do a quick print_r();. This looks like it's generating three separate arrays. I would like to be able to add the sums where the keys match.

Array ( [1] => 1399.24 )
Array ( [1] => 251.72 )
Array ( [2] => 209.79 )

Desired results

Array 1 = 1650.96
Array 2 = 209.79

Any insight is appreciated.

[TheoGB]

foreach ($array1 as $key => $value)
{
    if (isset($array2[$key])
    {
        $array1[$key] += $array2[$key]
    }
}

Hard to know if this will work without knowing how big your arrays are and how many there are but you can probably adapt it.

[NogDog]

Is this what you mean/need?

<?php
$data = array(
   array(1 => 1399.24),
   array(1 => 251.72),
   array(2 => 209.79)
);
echo "<pre>".print_r($data,true)."</pre>\n";
$sums = array();
foreach($data as $arr) {
   foreach($arr as $key => $val) {
      $sums[$key] = (!empty($sums[$key])) ? $sums[$key] + $val : $val;
   }
}
echo "<pre>".print_r($sums, true)."</pre>";

Output:

Array
(
    [0] => Array
        (
            [1] => 1399.24
        )

[1] => Array
    (
        [1] => 251.72
    )

[2] => Array
    (
        [2] => 209.79
    )

)

Array
(
    [1] => 1650.96
    [2] => 209.79
)

[gwerner]

NogDog, you nailed it! That works like a charm. I had a couple of other issues brewing, but your solution fit perfectly.

Thanks for the help. Hopefully it didn't take you too long to come up with that.