public function zUnionStore($destination, array $keys, array $weights = null, $aggregate = null)
{
$destination = array($destination, count($keys));
$destination = array_merge($destination, $keys);
if (!empty($weights)) {
$destination[] = 'WEIGHTS';
$destination = array_merge($destination, $weights);
}
if (!empty($aggregate)) {
$destination[] = 'AGGREGATE';
$destination[] = $aggregate;
}
return $this->__call('zUnionStore', $destination);
}