Group rows by one column value, sum another column and count occurrences

Question

I've build quite complicated array that contains other arrays with user mails and 'coins' values. I need to remove and count duplicated mails and merge 'coins' values.

Array (
    [0] => Array ( [mail] => [email protected] [coins] => 25000.00 ) 
    [1] => Array ( [mail] => [email protected] [coins] => 500000.00 ) 
    [2] => Array ( [mail] => [email protected] [coins] => 10000.00 ) 
    [3] => Array ( [mail] => [email protected] [coins] => 10000.00 )
    [4] => Array ( [mail] => [email protected] [coins] => 20000.00 )
)

So the output would look like:

[email protected] (2), 35000.00 coins
[email protected] (2), 510000.00 coins
[email protected] (1), 20000.00 coins

Thank you so much!

Since this question doesn't show any research effort, I taken the appropriate course of action and downvoted this question. — mickmackusa
– mickmackusa ♦, Commented May 6, 2020 at 12:04
SO is a Q&A site, not a code factory or "get your homework done". Please try it yourself first and then ask if you got stuck with an error. — Banana
– Banana, Commented May 7, 2020 at 9:28
Very, very related question: Group row data in a 2d array and calculate average of a column in each group — mickmackusa
– mickmackusa ♦, Commented Jan 7, 2024 at 4:07

Kavacky · Accepted Answer · 2020-05-06 11:30:34Z

1

$grouped = [];
foreach ($array as $item) {
    $email = $item['mail'];
    if (empty($grouped[$email])) {
        $grouped[$email] = ['count' => 0, 'sum' => 0];
    }

    $grouped[$email]['count']++;
    $grouped[$email]['sum'] += $item['coins'];
}

foreach ($grouped as $email => $data) {
    echo $email . '(' . $data['count'] . ') ' . $data['sum'] . ' coins';
}

edited May 6, 2020 at 11:30

Kavacky

485 bronze badges

answered May 6, 2020 at 11:20

u_mulder

54.8k5 gold badges54 silver badges72 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

mickmackusa · Accepted Answer · 2020-05-06 12:23:00Z

Group the data by assigning temporary associative keys (mail values) to a new result array.
While iterating, determine if you are processing the first occurrence of a mail value or not by calling isset() on the mail key of the result array.
If this is the first instance of the mail, set all of the values in the subarray.
If this is not the first instance of the mail value, adjust the pre-existing subarray.
After looping, use printf() to concisely format your data as desired.

In case the float output syntax is unfamiliar, read this.

Code: (Demo)

$array = [
    ['mail' => '[email protected]', 'coins' => '25000.00'],
    ['mail' => '[email protected]', 'coins' => '500000.00'],
    ['mail' => '[email protected]', 'coins' => '10000.00'],
    ['mail' => '[email protected]', 'coins' => '10000.00'],
    ['mail' => '[email protected]', 'coins' => '20000.00'],
];

$result = [];
foreach ($array as ['mail' => $mail, 'coins' => $coins]) {
    if (!isset($result[$mail])) {
        $result[$mail] = [1, $coins];  // declare the data for the first instance of mail
    } else {
        ++$result[$mail][0];          // increment the running count
        $result[$mail][1] += $coins;  // add coins to running total
    }
}

foreach ($result as $mail => $row) {
    printf("%s (%d), %.2f coins\n", $mail, ...$row);  // unpack the row with the splat operator (...)
}

Output:

[email protected] (2), 35000.00 coins
[email protected] (2), 510000.00 coins
[email protected] (1), 20000.00 coins

Collectives™ on Stack Overflow

Group rows by one column value, sum another column and count occurrences

2 Answers 2

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related