Online PHP editor | refs for bvEYC

<?php $array = [ '2017-05-01' => [ 'DC' => [ 'IT' => [90, 0], 'DE' => [18, 315, 40, '', 69, 211], 'Other' => [107, 46, '', '', 27, 22] ] ], '2017-05-02' => [ 'DC' => [ 'IT' => [70, 40, 55], 'DE' => ['', 31, 4, '', 9], 'Other' => [1107, 12, 0, 20, 1, 11, 21] ] ], 'fringe case' => [ 'DC' => [ 'IT' => [], 'DE' => ['', '', '', 99], 'Other' => ['', 99] ] ] ]; var_export( array_map( fn($dateSet) => array_map( fn($dcSet) => array_map( function ($set) { if (!$set) { return 0; } sort($set); $count = count($set); $mid = intdiv($count, 2); if ($count & 1) { return $set[$mid]; } return ((int)$set[$mid - 1] + (int)$set[$mid]) / 2; }, $dcSet ), $dateSet ), $array ) );