/**
* Return a list of recommendations.
*
* @param string $for - the item we want recommendations for
* @param object $strategy
*
* @return array - return a list of identifier ordered by closest
*/
public function recommend($for, $strategy = null)
{
if ($strategy === null) {
$strategy = new Cosine();
}
$distances = [];
foreach ($this->set as $key => $itemData) {
if ($key == $for) {
continue;
}
$distance = $strategy->run($itemData, $this->set[$for]);
if ($distance === false) {
continue;
}
$distances[$key] = ['key' => $key, 'value' => $distance];
}
if (!count($distances)) {
return false;
}
$this->sort($distances, true);
$data = [];
foreach ($distances as $article) {
if ($article['value'] == 0) {
continue;
}
$data[] = $article['key'];
}
return $data;
}
public function testCosinSimilarity()
{
$cosin = new Cosine();
$users = json_decode(file_get_contents(__DIR__ . '/../fixtures/perfect_users.json'), true);
$score = $cosin->run($users['Clara'], $users['Robert']);
$this->assertEquals(0.064846541429478, $score);
}