ARC2_IndexUtils is a plugin for Arc providing a few simple functions for processing rdf/json - shaped data:

• ARC2_IndexUtils::filter() takes 2 parameters: a data array, and an associative array of filters. you might use it like this:

  ARC2_IndexUtils::filter($data, array('property'=>  create_function('$u,$p,$os','return $p=="http://xmlns.com/foaf/0.1/name";'), ))
  

  Which would return a data array with only those statements having http://xmlns.com/foaf/0.1/name in the property position.

• ARC2_IndexUtils::merge takes a variable length list of parameters, where each parameter is an rdf/json style data array, and merges them into one data array.
• ARC2_IndexUtils::diff takes a variable length list of parameters, returning a data array consisting only of statements from the first array that didn’t exist in any of the subsequent arrays
• ARC2_IndexUtils::intersect
  takes a variable length list of parameters, returning a data array consisting only of statements from the first array that also exist in all of the subsequent arrays
• ARC2_IndexUtils::reify reifies an rdf/php data array (you might use this for creating a changeset, or for making provenance statements about your triples)
• ARC2_IndexUtils::dereify dereifies an rdf/php data array (reified statements can be hard to read, you might want to dereify them to see what they say more easily)