/**
* Returns objects of the same class and with similar ratings as the current rateable object.
*
* This implementation is based on the
* OpenSlopeOne project by Chaoqun Fu, http://code.google.com/p/openslopeone/.
*
* @param BaseObject $object The rateable object for which to return other recommended object
* @param int $limit The number of recommendation objects which should be returned. Use NULL for returning all recommended objects
* @return array of sfRecommendationObject objects which wrap the recommended objects
*/
public function getRecommendations(BaseObject $object, $limit = NULL)
{
$parser = new sfPropelSlopeOneSqlParser();
$slopeQuery = 'SELECT item2_id AS id,
SUM(rating/times) AS rating
FROM sf_slope_one
WHERE item1_id = :item_id AND
item1_model = :item_model AND
item1_model = item2_model
GROUP BY item2_id
ORDER BY rating DESC';
$slopeQuery .= isset($limit) ? ' LIMIT ' . $limit : '';
$connection = Propel::getConnection();
$statement = $connection->prepare($parser->parse($slopeQuery));
$statement->execute(array('item_id' => $object->getId(), 'item_model' => get_class($object)));
$ratings = array();
while ($result = $statement->fetch()) {
$ratings[$result['id']] = $result['rating'];
}
$objects = call_user_func(array(get_class($object->getPeer()), 'retrieveByPKs'), array_keys($ratings));
foreach ($objects as &$object) {
$object = new sfSlopeOneRecommendation($object, $ratings[$object->getId()]);
}
return $objects;
}
/**
* Returns recommended objects which the user has not rated based on his/her
* rating of other objects.
*
* This implementation is based on the
* OpenSlopeOne project by Chaoqun Fu, http://code.google.com/p/openslopeone/.
*
* @param BaseObject $object The user for which to return the recommendations
* @param string $model The name of the class for which to return recommendations
* @param int $limit The number of recommendation objects which should be returned.
* Use NULL for returning all recommended objects
* @return array of sfRecommendationObject objects which wrap the recommended objects
*/
public function getRecommendations(BaseObject $object, $model, $limit = NULL)
{
$parser = new sfPropelSlopeOneSqlParser();
$slopeQuery = 'SELECT sf_slope_one.item2_id AS id,
SUM((%ratings%.%rating% * sf_slope_one.times) - sf_slope_one.rating)/
SUM(sf_slope_one.times) AS rating
FROM sf_slope_one, %ratings%
WHERE %ratings%.%rater_id% = :rater_id AND
%ratings%.%rateable_model% = :item_model AND
%ratings%.%rateable_id% = sf_slope_one.item1_id AND
%ratings%.%rateable_model% = sf_slope_one.item1_model AND
sf_slope_one.item2_id NOT IN (SELECT %ratings%.%rateable_id%
FROM %ratings%
WHERE %ratings%.%rater_id% = :rater_id)
GROUP BY item2_id
ORDER BY rating DESC';
$slopeQuery .= isset($limit) ? ' LIMIT ' . $limit : '';
$connection = Propel::getConnection();
$statement = $connection->prepare($parser->parse($slopeQuery));
$statement->execute(array('rater_id' => $object->getId(), 'item_model' => $model));
$ratings = array();
while ($result = $statement->fetch()) {
$ratings[$result['id']] = $result['rating'];
}
$modelObject = new $model();
$objects = call_user_func(array(get_class($modelObject->getPeer()), 'retrieveByPKs'), array_keys($ratings));
foreach ($objects as &$object) {
$object = new sfSlopeOneRecommendation($object, $ratings[$object->getId()]);
}
return $objects;
}
