gistfile1.php

foreach ($_GET as $get) {
  foreach ($tax_names as $tax) {
    if (isset($_GET['spg_'.$tax->name])) {
      $remove_filter = '<input type="button" onclick="window.location=\''.get_the_permalink().'\';" class="button button-submit" value="'.__("Remove Filter","infiwebs").'"/>';
      $display = 'tax_query';
      $posts_from_filter[] = array(
        'taxonomy' => $tax->name,
        'field' => 'slug',
        'terms' => $_GET['spg_'.$tax->name]
      );
    }
  }
}