PHP: substract values of 2 arrays of different length - php

Question

Well, I've got two following arrays:
$incomesArr = [
['1605564000' => 121],
['1605736800' => 3.50],
];
$expensesArr = [
['1605736800' => 3.50],
['1605736800' => 3.50],
['1605564000' => 28],
['1605936000' => 50]
];
As you can see from the variable names, these are the expenses and incomes for the current date (it is a timestamp). All I want to do is to generate the "Revenue" data by substracting value of $expensesArr from $incomesArr with corresponding date, and if there is no date, then substract from 0. Also, if there is no corresponding date in the $expensesArr, then substract nothing (or 0).
Basically, I want to achieve the following result:
['1605564000', 93]; // 121 - 28 = 93
['1605736800', -3.50] // 3.50 - 3.50 - 3.50 (since both expenses are for the same date)
['1605936000', -50] // 0 - 50, since there is no income for that day.
Please note, that the output result should be in the ['key', 'value'] format, not the ['key' => 'value'], since I send these data to jQuery Flot (displaying graphs).
I carry about the performance, since there may be kind of significant amount of data and the best way for me to achieve this is without foreach loop, however if it is the only possible option, then foreach it is!
Any help is highly appreciated. Thank you in advance!
P.S. If it would help, then I do this in Laravel, however I don't think that there is a special helper exactly for that, since I already examined the Laravel documentation multiple times :)
My previous attempt was a bit confusing and scary, but here it is:
$newArr = array_merge([$incomesArr, $expensesArr]);
foreach ($incomesArr as $k => $v){
$sub = $v - $expensesArr[$k];
// this is like : array1[1]-array2[1]
}
$finalArr = [];
foreach($newArr as $key => $value) {
var_dump($value);
foreach ($value as $key => $val) {
$finalArr[$key] = ($val[$key] ?? 0) - ($val[$key] ?? 0);
}
}

Answer 1

$incomesArr = [
['1605564000' => 121],
['1605736800' => 3.50],
];
$expensesArr = [
['1605736800' => 3.50],
['1605736800' => 3.50],
['1605564000' => 28],
['1605936000' => 50]
];
// get data
$dataArr = [];
foreach([-1 => $expensesArr, 1 => $incomesArr] as $ratio => $list){
foreach($list as $value){
$time = key($value);
$dataArr[$time] = ($dataArr[$time] ?? 0) + ($value[$time] * $ratio);
}
}
// convert to your format
$finalArr = [];
foreach($dataArr as $time => $value){
$finalArr []= [$time, $value];
}
print_r($finalArr);
Output
Array
(
[0] => Array
(
[0] => 1605736800
[1] => -3.5
)
[1] => Array
(
[0] => 1605564000
[1] => 93
)
[2] => Array
(
[0] => 1605936000
[1] => -50
)
)

Answer 2

I would split it into two functions like so:
$incomesArr = [
['1605564000' => 121],
['1605736800' => 3.50],
];
$expensesArr = [
['1605736800' => 3.50],
['1605736800' => 3.50],
['1605564000' => 28],
['1605936000' => 50]
];
function getTotalByKey($inputArray, $inputKey)
{
$sum = 0;
foreach ($inputArray as $subArray)
foreach ($subArray as $key => $value) {
$sum += $key === $inputKey ? $value : 0;
}
return $sum;
}
function getProfitByKey($incomesArray, $expensesArray, $key){
return getTotalByKey($incomesArray, $key) - getTotalByKey($expensesArray, $key);
}
$profit = getProfitByKey($incomesArr, $expensesArr, 1605736800); // Outputs -3.5

Answer 3

$incomesArr = [
['1605564000' => 121],
['1605736800' => 3.50],
];
$expensesArr = [
['1605736800' => 3.50],
['1605736800' => 3.50],
['1605564000' => 28],
['1605936000' => 50]
];
$tmp = [];
$final = [];
foreach ($incomesArr as $pair)
{
foreach ($pair as $date => $amount)
{
$tmp[$date] = ($tmp[$date] ?? 0) + $amount;
}
}
foreach ($expensesArr as $pair)
{
foreach ($pair as $date => $amount)
{
$tmp[$date] = ($tmp[$date] ?? 0) - $amount;
}
}
print_r($tmp);
foreach ($tmp as $date => $amount)
{
$final[] = [$date, $amount];
}
print_r($final);
Output
Array
(
[1605564000] => 93
[1605736800] => -3.5
[1605936000] => -50
)
Array
(
[0] => Array
(
[0] => 1605564000
[1] => 93
)
[1] => Array
(
[0] => 1605736800
[1] => -3.5
)
[2] => Array
(
[0] => 1605936000
[1] => -50
)
)