Removing container from wp_nav_menu not working

[SOLVED]
IT DOES NOT WORK when you are referring to an inexisting location. e.g. when you copied the code from somewhere else, or you haven’t created your menu or location yet in the dasboard.

e.g. remove “, ‘theme_location’ => ‘primary'” from the following code:

    wp_nav_menu( array( 'container'=> false, 'menu_class'=> false, 'menu_id'=> 'ia_toplevel', 'theme_location' => 'primary' ) );

so it shoult look like

    wp_nav_menu( array( 'container'=> false, 'menu_class'=> false, 'menu_id'=> 'ia_toplevel' ) );

It works fine WITHOUT container in my website SocialBlogsiteWebDesign.com