My post list design is good. But the list sorted by popular and it not working. Please see my code below and shed some light on it. I want to sort my posts by their popularity by views of last 7 days. Here is my code:

<?php
$params = array(
    'orderby'             => 'popular',
    'post_type'           => 'post',
    'ignore_sticky_posts' => 1,
    'posts_per_page'      => 4,
    'no_found_rows'       => true,
);
$query_data = pixwell_query($params);
while ($query_data->have_posts()) :
    $query_data->the_post();
    pixwell_post_list_4();
endwhile;
?>