Wordpress create post with categories

add_action( 'init', 'article_fn' );

function article_fn() {

register_post_type( 'article', array(

  'labels' => array(

    'name' => 'Article',

    'add_new_item' => 'Add new article',

    'add_new' => 'Add new article',

    'view_item' => 'View Article',

    'singular_name' => 'Article',

    'set_featured_image' => 'Set article featured image',

    'search_items' => 'Search Article',

    'menu_name' => 'All Articles',

    'name_admin_bar' => 'View all articles'

   ),

  'description' => 'Article which we will be discussing on this blog.',

  'public' => true,

  'taxonomies' => array( 'category' ),

  'menu_position' => 2,

  'supports' => array( 'title', 'editor', 'custom-fields','author','thumbnail','excerpt','trackbacks','comments','revisions','page-attributes','post-formats' )

));

}