i think this can be actually a good idea and I think that would require a new feature type implementation.
Specifically I think you could leverage the existing data structures ( such TermVector) to calculate the matrix and then perform the calculations you need. Or maybe there is space for even a new optional data structure in the index, to support matrix calculation ( it's been a while I don't take a look to codecs and index file formats). ----- --------------- Alessandro Benedetti Search Consultant, R&D Software Engineer, Director Sease Ltd. - www.sease.io -- Sent from: http://lucene.472066.n3.nabble.com/Solr-User-f472068.html
