public static function pruneNarrowConcepts($concepts)
{
// Build a map with paths as keys
$concepts = array_combine(Concept::toPathArray($concepts), $concepts);
// Paths are sorted in advance to keep search O(n)
ksort($concepts);
// With sorting, the first element can't be a child
$broad = current($concepts);
next($concepts);
// Start prunning concepts narrower than current broad one
while ($concept = current($concepts)) {
if ($concept->isNarrowerThan($broad)) {
unset($concepts[key($concepts)]);
} else {
// End of prunable childs, beginning of a new concept
$broad = $concept;
next($concepts);
}
}
return array_values($concepts);
}
public static function childOfConcepts($databox_id, array $concepts)
{
return new self($databox_id, Concept::toPathArray($concepts));
}