add another variable to php function

I have added this snippet to functions.php to be able to order Slider Revolution slides:

// orderby slideshows

function modify_slider_order($query, $slider_id) {

// only alter the order for slider with "x" ID
// https://tinyurl.com/zb6hzpc

if($slider_id == 17 ) {

    // Custom Meta key/name
    $query['meta_key'] = 'numeric_order';

    // Order by Custom Meta values
    $query['orderby'] = 'numeric_order';

    // Calculate order based on:
    // 'NUMERIC', 'CHAR', 'DATE', 'DATETIME', 'TIME'
    $query['meta_type'] = 'NUMERIC';

}


return $query;

}

add_filter(‘revslider_get_posts’, ‘modify_slider_order’, 10, 2);

I would like to reference either all slideshows, or another (id=16). I have tried commenting out the "if($slider_id…" part, and also tried adding the other slide id separated by a comma next to the 17, but WP is kicking up errors. Thank you.