array

[satifal]

foreach ($data['categories'] as $categories) {
    foreach ($categories['groups'] as $groups) {
        foreach ($groups['subgroups'] as $subgroups) {
            echo "subgroupCode->".$subgroups['subgroupCode'].", subgroupDescription->".$subgroups['subgroupDescription']."<br/>";
        }
    }
}