WP_filter

WP_filter.php

<?php
query_posts("showposts=40&meta_key=Materia_1&orderby=title&order=DESC"); 
$coma;
if (have_posts()) : while (have_posts()) : the_post(); 
    $do_not_duplicate = $post->ID;
    $materias[] =  get_post_meta(get_the_ID(), 'Materia_1', true);
    //$found = explode("," , get_post_meta(get_the_ID(), 'Materias', true));    
    $coma = get_post_meta(get_the_ID(), 'Materias', true);
endwhile;
//$found = array_count_values($materias);
$materias = array_unique($materias);
echo $coma;
foreach($materias as $materia){
    //echo $materia."<br/>";    
    echo "<h4><a href=\"http://bnphu.gob.do/disepedi/libros-por-materia/?autor=".$materia."\">".$materia."(".$coma.")</h4>";
}
    
?>

<?php else: ?>