/*
 * Setup the Index page, main query adjustments
 *
 * If we're viewing the site index get the first 5 posts
 * from the "Marquee" category (home-slider), ordered
 * by our meta value and ignoring any sticky stuff.
 *
 */
function mnsu_index_query( $query ) {
    if ( is_home() && $query->is_main_query() ) {
        // Set paging to 5
        $query->set( 'posts_per_page', '5' );
        $query->set( 'ignore_sticky_posts', 1 );
        // Get posts from the Marquee category
        $tax_query = array (
            array(
                'taxonomy' => 'placements',
                'terms' => array( 'home-slider' ),
                'field' => 'slug',
            )
        );
        $query->set( 'tax_query', $tax_query );
        $query->set( 'meta_key', 'mnsu_placement_home-slider' );
        $query->set( 'orderby', 'meta_value_num' );
        $query->set( 'order', 'ASC' );
    }
}
add_action( 'pre_get_posts', 'mnsu_index_query' );