Magento PHP script to delete all values of an attribute

magento-delete-attribute-options.php

<?php
$attribute_code = 'ATTRIBUTE_NAME';
$attribute = Mage::getModel('eav/config')->getAttribute('catalog_product', $attribute_code);
$options = $attribute->getSource()->getAllOptions();

$optionsDelete = array();

foreach($options as $option) {
    if ($option['value'] != "") {
        $optionsDelete['delete'][$option['value']] = true;
        $optionsDelete['value'][$option['value']] = true;
    }
}

$installer = new Mage_Eav_Model_Entity_Setup('core_setup');
$installer->addAttributeOption($optionsDelete);
?>

Thank you for example, it helped me to do the same thing on Magento 2: https://gist.github.com/bh-ref/2a788f206f8c3d833e43