Group matched array values - php

Question

Program:
while($i<=$row) {
echo $arr[$i][1].$arr[$i][4]
}
Output
Product Code Qty
KC_DRINK_TASTY_CASE 1
KC_DRINK_TASTY_CASE 1
KC_DRINK_TASTY_CASE 1
KC_DRINK_TASTY_CASE 1
KC_SUNGLASSES_BK 1
KC_SUNGLASSES_BK 1
KC_SUNGLASSES_BE 1
KC_SUNGLASSES_BE 1
KC_SUNGLASSES_OE 1
KC_SUNGLASSES_OE 1
KC_SUNGLASSES_RD 1
KC_SUNGLASSES_RD 1
KC_SUNGLASSES_WE 1
KC_SUNGLASSES_WE 1
I want it to output
KC_DRINK_TASTY_CASE 4
KC_SUNGLASSES 10
so that it group product code excluding last underscore and sum their quantity

Answer 1

If $arr looks something like this:
$arr = array(
array('{something}', 'KC_DRINK_TASTY_CASE', '{something}', '{something}', 1),
array('{something}', 'KC_SUNGLASSES_BK', '{something}', '{something}', 1),
// ...
);
Then you can get the output what you what like this:
// we'll store counts here
$result = array();
foreach ($arr as $row) {
$product = $row[1];
$qty = $row[4];
// figure out where the last underscore is and chop off everything that follows it
// this is VERY brittle. If the product ends up with a name like _SOMEKEY you'll end
// up with an empty key. Not good. Probably not a huge issue, but buyer beware
$_product = substr($product, 0, strrpos($product, '_'));
if (isset($result[$_product])) {
$result[$_product] += $qty; // we already started counting
} else {
$result[$_product] = $qty; // not started counting this product yet, start it
}
}
// now print your result:
foreach ($result as $id => $qty) {
echo $id, "\t", $qty, PHP_EOL;
}