Undefined variable & issue with smof_data

The variable $alignment is only being set conditionally by the following lines:

if ( metadata_exists( 'post', $post_id, 'pyre_page_title_text_alignment' ) && 
             get_post_meta( get_queried_object_id(), 'pyre_page_title_text_alignment', TRUE ) != 'default' 
) {
    $alignment = get_post_meta( $post_id, 'pyre_page_title_text_alignment', TRUE );
} elseif ( $smof_data['page_title_alignment'] ) {
    $alignment = $smof_data['page_title_alignment'];
}

If neither the if() nor the elseif() conditions are met, the variable is never set. Probably there is an initialisation with a default value missing:

$alignment="center";

This should be placed above the aforementioned lies of code.