Question

Trying to group an array depending on whether it’s index is divisible by there. I’ve tried various combinations of for loops and foreach loops and if($i % 3 == 0) … But, it’s not outputting the way I need it.

Here is a greatly simplified array (the original data contains a lot of highly sensitive information…)

The original array looks similar to this:

$item[0]['Section 1']['Item 2'] => 1334;
$item[1]['Section 2']['Item 3'] => 15454;
$item[2]['Section 3']['Item 4'] => 1452;
$item[3]['Section 4']['Item 5'] => 1341;
$item[4]['Section 5']['Item 6'] => 1788655;
$item[5]['Section 6']['Item 7'] => 13;
$item[6]['Section 7']['Item 8'] => 142;
$item[7]['Section 8']['Item 9'] => 15678;
$item[8]['Section 9']['Item 10'] => 15542;
$item[9]['Section 10']['Item 11'] => 16578;
$item[10]['Section 11']['Item 12'] => 18452;
$item[11]['Section 12']['Item 13'] => 16565;

I’m trying to group every 3 records, like this:

$newitem[0]['Section 1']['Item 2'] => 1334;
$newitem[0]['Section 2']['Item 3'] => 15454;
$newitem[0]['Section 3']['Item 4'] => 1452;
$newitem[1]['Section 4']['Item 5'] => 1341;
$newitem[1]['Section 5']['Item 6'] => 1788655;
$newitem[1]['Section 6']['Item 7'] => 13;
$newitem[2]['Section 7']['Item 8'] => 142;
$newitem[2]['Section 8']['Item 9'] => 15678;
$newitem[2]['Section 9']['Item 10'] => 15542;
$newitem[3]['Section 10']['Item 11'] => 16578;
$newitem[3]['Section 11']['Item 12'] => 18452;
$newitem[3]['Section 12']['Item 13'] => 16565;

Answer 1

This should do it:

$newindex = 0;
$newitem = array();
for($i = 0; $i < count($item); ++$i)
{
    $newindex = (int) $i / 3;
    if(!isset($newitem[ $newindex ]))
        $newitem[ $newindex ] = array();

    $newitem[ $newindex ] = array_merge($newitem[ $newindex ], $item[ $i ]);
}

Link to output (dump of $newitem)

The trick is (int) $i / 3, which takes $i, divides it by 3, then casts to int which truncates any decimal places.