How to sum (sub total) array based on two keys? - php

Question

I have array with below values
Array
(
[0] => Array
(
[order_date] => 2016-01-01
[sku] => RK101
[qty] => 2
)
[1] => Array
(
[order_date] => 2016-01-01
[sku] => RK101
[qty] => 5
)
[2] => Array
(
[order_date] => 2016-01-01
[sku] => RK102
[qty] => 4
)
[3] => Array
(
[order_date] => 2016-01-02
[sku] => RK101
[qty] => 2
)
[4] => Array
(
[order_date] => 2016-01-02
[sku] => RK101
[qty] => 2
)
)
and i want to sum the array, first by date and then by sku, i want result like below
Array
(
[2016-01-01] => Array
(
[RK101] => Array
(
[qty] => 7
)
[RK102] => Array
(
[qty] => 4
)
)
[2016-01-01] => Array
(
[RK101] => Array
(
[qty] => 4
)
)
)
i have explore stack overflow and found many post that calculates the sum based on one key, by in this case i want to sum the array values based on date first and then by sku.
please help with the same

Answer 1

try below solution:
<?php
echo '<pre>';
$array = Array
(
'0' => Array
(
'order_date' => '2016-01-01',
'sku' => 'RK101',
'qty' => 2
),
'1' => Array
(
'order_date' => '2016-01-01',
'sku' => 'RK101',
'qty' => 5
),
'2' => Array
(
'order_date' => '2016-01-01',
'sku' => 'RK102',
'qty' => 4
),
'3' => Array
(
'order_date' => '2016-01-02',
'sku' => 'RK101',
'qty' => 2
),
'4' => Array
(
'order_date' => '2016-01-02',
'sku' => 'RK101',
'qty' => 2
)
);
$new_array = array();
foreach ($array as $a) {
if (!isset($new_array[$a['order_date']][$a['sku']]['qty'])) {
$new_array[$a['order_date']][$a['sku']]['qty'] = 0;
}
$new_array[$a['order_date']][$a['sku']]['qty'] += $a['qty'];
}
print_r($new_array);
output:
Array
(
[2016-01-01] => Array
(
[RK101] => Array
(
[qty] => 7
)
[RK102] => Array
(
[qty] => 4
)
)
[2016-01-02] => Array
(
[RK101] => Array
(
[qty] => 4
)
)
)

Answer 2

Here is another solution that gives you a slightly different output, which may or may not be preferred.
$results = array();
$myNums = array(
array(
'order_date' => '2016-01-01',
'sku' => 'RK101',
'qty' => 2,
),
array(
'order_date' => '2016-01-01',
'sku' => 'RK101',
'qty' => 1,
),
array(
'order_date' => '2016-01-02',
'sku' => 'RK101',
'qty' => 2,
),
);
foreach ($myNums as $num) {
$key = "{$num['order_date']}|{$num['sku']}";
if (! array_key_exists($key, $results)) {
$results[$key] = 0;
}
$results[$key] += $num['qty'];
}
var_dump($results);
/*
var_dump gives the following...
Array
(
[2016-01-01|RK101] => 3,
[2016-01-02|RK101] => 2,
)*/