woocommerce_grouped_product_columns filter-hook . WC 1.0

Usage

add_filter( 'woocommerce_grouped_product_columns', 'filter_function_name_526', 10, 2 );
function filter_function_name_526( $array, $product ){
	// filter...

	return $array;
}

$array

-

$product

-

Where the hook is called

$grouped_product_columns = apply_filters(
	'woocommerce_grouped_product_columns',
	array(
		'quantity',
		'label',
		'price',
	),
	$product
);

Where in WP core the hook is used WooCommerce