Set Taxonomy of Post Author in Gravity Forms

// SET TAXONOMY OF AUTHOR

add_action('gform_post_submission', 'ounce_gform_post_submission', 10, 2);
function ounce_gform_post_submission($entry, $form) {

// if no post was created, return
    if(!$entry['post_id'])
        return;

// name_ID = the ID of the author in the author custom taxonomy
    if ($entry["1"] == 'Poe') {
        $name_ID  = "12";
    } elseif ($entry["1"] == 'King') {
        $name_ID  = "24";
    } elseif ($entry["1"] == 'Lewis') {
        $name_ID  = "48";
    } elseif ($entry["1"] == 'Tolkien') {
        $name_ID  = "96";
    }
    $term_id = $name_ID;

// the slug name of the taxonomy you set up
    $taxonomy = 'author';


// if we have a taxonomy and a field id, add term to post
    if($taxonomy && $term_id)
        ounce_add_term_to_post($taxonomy, $term_id, $entry['post_id']);
}

// add term from taxonomy to post
function ounce_add_term_to_post($taxonomy = "categories", $term_id, $post_id) {

    $terms = get_terms($taxonomy, array('hide_empty' => 0));

    foreach($terms as $term) {

        if($term->term_id == $term_id)
            $result = wp_set_object_terms($post_id, (int) $term_id, $taxonomy, false);
    }
}